As expected, the interview was by far the easiest part of this whole journey! On entry (having remembered reading on here not to wait in the queue in the lobby and go straight to the desk) I skipped the queue and got sent straight up to the waiting room. I was seen very quickly after arriving by the man who would take my paperwork. He took my appointment confirmation, passport, US pictures, birth certificate, police certificate from the U.K. and Spain, i134, employment verification and pay stubs.
I sat back down and this wait took over an hour but I believe the system went down today so that explains it! Once I finally got to my actual interview I spoke with the officer for less than a minute and he told me I was approved and to expect my visa within the week!