sooo... I had my interview yesterday and it went well... here comes the full, overly detailed account, may it help those who come after me
I took the train from Hamburg to Frankfurt dep. 00:25 arrival 5:29 - saved money on staying overnight, but paid with grogginess.
At the train station in Frankfurt, I put my cellphone in the locker and paid 2 Euro for 24 hours... The English instructions actually said that you were not allowed to put cellphones or money and jewelry in there, but the German instructions didn't say that, and so I risked it (especially since it's not the nicest phone and I can't use it in the US anyways (wrong frequency)) And it was still there in the afternoon.
I bought an all day ticket for the public transport system in innercity Frankfurt (zone 50, includes doctor and embassy) for 5.40 Euro. Then I took the S train to the innercity and searched for my Bank (Dresedner Bank) and found it eventually and I checked out how much money I had and took out all I could (not much) just to make sure I had enough. I found the Lidl store, but it was open yet of course (I had looked up grocery stores in Frankfurt ahead of time and put them on the little map that the embassy had sent in Packet 4) I then took the subway to the doctor and got there around 7am and I had been there earlier if I hadn't purposefully walked the wrong way for a bit

I was the first one there, but soon others came.. . The door was locked and it said it opens at 8, but I was supposed to be there at 7:30 and sure enough a little after 7:30, the door was buzzed open. I was first in line (there were about 4-5 others by then) and the whole medical took about one or one and a half hours.
-First waiting, then going upstairs
-Fill out a form on medical history
-Payment (125 Euro), turn in vaccination records, sign for permission to take HIV test
-then in the basement - urin test, xray, blood test (HIV),
-then upstairs - doctor's exam with clothes off except underwear
(breathe in, breathe out, stick your tongue out) and eye sight testing
I was informed that I had to get my polio and tetanus vaccination freshened up since it's good for 10 years and I had mine in 96 last time, but that wouldn't be a problem. Also, the doctor took my word for it when I said I had chickenpox as a kid (I called beforehand and asked if he would) so... now I still have to see a doctor (in 2 days I will) and get those vaccinations which I will fax proof of to Frankfurt to the doctor and then they will send in their stuff to the embassy, so it's just a delay of a few days.
Since I had sufficient time, I stopped by Lidl to get some food an drink, as I hadn't packed enough for the day
Then off to the Embassy with the Subway and arrived right on time (9:30)
First to the line on the left where I showed my passport and appointment letter and got a number, then the line on the right where people were waiting to be waved in through security...
While i was waiting for security i saw a person getting back their cellphone from security personal upon leaving the embassy, which I thought curious since I was under the impression that they would send you away if you had one on you (and I warn you that I wouldn't risk it, since that's what they say in the letter, but it seems like they might make exceptions at times, also another ladies handbag was kept at security because she had something in it that wasn't allowed (not sure what)
Out of the security building to the next building which looked totally different than I imagined. Didn't see anybody at the desk and continued, was then approached by a lady from behind who asked to see my number and advised me on where to sit (in the back, to the right) I asked her for where the bathrooms are and she said behind the pink wall.
This building is sort of like an American Driver's License bureau except nicer. Very bright with a window roof and light colors and very clean. There's a coke vending machine and a stamp vending machine and some more stuff which i didn't really take notice of... lots of chairs (300?) in the middle, facing the right side, about 25 windows, mostly on the right side where interaction with the embassy employees took place. The bathroom door had a handle, but to my slight shock opened automatically upon approaching (also I now remember the door to the building was so heavy that I had trouble controlling it with one arm, and I'm by no means weak)
When I left the bathroom, I already noticed my number on the screen and went to window 20 something, (a German lady who started conversation in English, but was glad to see my German passport) gave her my DS 230 part II and passport, she gave me a paper that told me how to put my forms in the correct order (I had put them in order already as it tells you how to order them in packet 4) And the envelope which I would get my passport in - BTW.. the whole day I had to carry this huge envelope with me that had the x-ray of my chest... (about 16 inches by 16 inches (45 cm by 45 cm)) from my medical exam and I was instructed to carry it with me in my hand luggage when I went to the states and hand it over to the immigration officer. She then instructed me to pay at the next window.
I went there and I don't know where they guy was from, but he spoke English with some sort of accent I couldn't identify. He said "DENMARK

))" (which, I was born in Denmark, but why could he see that and not my German residence and passport?) "Did you come from Denmark today?" We had some small talk and it was hard to hear all he said, especially with the number of kids in the lobby that were not ashamed to vent their frustration at the waiting (one mom told her kid "tell 'em, you tell 'em") He asked me if was feeling sick, which i thought curious and said "no, why are you asking?" He said my face looked kinda.... and I told him i traveled over night, then he also pointed to the band aid on my arm and remembered himself that I probably had gone to a medical. He was nice and I paid 305 Euro (380 USD equivalent) , but when I went back to waiting I wondered if all his questions were supposed to make sure I wasn't drunk or on drugs (did my face really look that awful ?!?!?)
I then had to sit back down, got a stamp from the machine for my envelope and put on my parent's address since we're hoping to be there before we fly. I was called up again to another window eventually and there turned in my birth certificate and copy and police records and I-864s and the lady went over my DS-230 part I with me to make sure it was correct. She asked a few questions, like if the cosponsor was related to me, to which i said "no, he's a good friend of ours" (someone else had already asked that as well) She told me she didn't need my marriage certificate since she already had it and asked if i had been in armed service, which i hadn't (Zivildienst does not count) She gave me a paper with info on Social Security numbers and a booklet with info for greencard holders (funny to me since I hadn't been interviewed yet) She also asked when I was expecting to travel. I said I originally hoped to travel on the 29th of August, but since I wasn't sure if I'd make it, probably the 4th of Sept.... she put down the 4th of September and I wondered quietly if they process your stuff faster if you name an earlier date or why they ask.
She then told me to sit back down until the consular would call me up for the interview, which would happen by means of the same number I had all through my embassy stay. Then I waited again and noticed that the couple in front of me seemed to have some sort of difficulties (with embassy stuff) which were resolved however to their great relaxation. Eventually I was called up again, the consular officer, obviously American, started in German, to which I replied in German but soon he switched to English. He asked if I swore to the truthfulness of my info in the DS 230 part II and had me sign it, he took my index finger prints digitally and that was basically it. He said I would get my passport in about a week but that they would have to get the medical records first.
All in all it took about 1:30 hours at the embassy and I then went to get my cellphone from the main train station and waited 5 hours for my train ride... sooooooooo.....
we shall see how soon we can realize the trip

)))
thanks again to everyone here for bearing with me