If I won 20 million dollars this instant, then I would finish Pharmacy School, then I would try and do medical school, since ultimately the reason I didn't do it in the first place was because of money. With lack of money no longer being a problem, I would focus on a career in medicine and continue living my life just as I am now.
I definitely would not go crazy, and I would also choose to accept it in increments over the years, rather than a lump sum. And finally, and most importantly, I would accept it anonymously if I could.