At worst you will be denied and have to appeal, and from what I understand most people win when they appeal...likewise its very common to be denied when you first apply. It is hard to say what your individual odds are...but all I can say is try and be as patient as you can, though its easier said than done because at least for me the process has been very slow and stressful.

Also they can look at your medical records and dig them up, I don't think it depends on you having to remember all the doctors I think they can look that stuff up it just makes things go smooother if you give them all the records/doctors names and such you can think of.