Getting a doctor's note..

So this is the first time I've missed an exam ever! I wasn't feeling well throughout the day but took some pain meds and thought I would go write the midterm exam anyway (which was at 6pm). However, as time went on, my condition worsened to the point where I was in a lot of pain and started throwing up. Anyway, I e-mailed by prof right away about this. However, I now need a doctor's note. The thing is, I'm feeling better now - I'm still a little drained, but most of my symptoms are gone. And I heard that the doctors only give out notes if you go see them WHILE you are sick. So what do I do now? Because if they don't, then it's totally unfair because I really was in a lot of pain at the time. If I had realized this before, I would have mustered up the strength to go get checked out but it didn't occur to me that the doctor would need proof of the illness. Anyway, the whole thing is silly though. Going to see a doctor while you are puking and writhing in pain to get a note. Surely my doctor will write me the damn note right?