My interview was about 6 weeks after my medical but that's only because it took me a while to find an available appointment online (I was checking every day as well). This wasn't too bad though as it allowed me to get my Covid vaccine in that time before they sent my medical file to the embassy.
If you can book them closer together then that would be better as it gives you more time to sort things out before travelling to the USA. I think it was advised that you should have at least 10 working days between the medical and interview but this could have changed since then.