Take it slow. Bring a notebook and just try to follow along as best you can. You won't get it all right away, it will take time.
I once equated diagnosis with being dropped in the middle of Japan with no translation dictionary and no language lessons. It really will be like learning anew language -- you'll have to learn the terms, understand the disease, and get a feel for everything before you'll be able to ask quesitons.. You can take it slowly and you'll get there. During the next few months, everytime you have a question write it in your notebook so you can ask them next time. You'll forget your questions when you are looking at the doctor if you don't have a list.
Keep coming here, there is so much to learn and we can help support you as you wrap your brain around this. ((((HUGS))))