The number of hairs shed by a "normal" person on a daily basis varies between 50-150 hairs/day. You will never go a day in your life without shedding some hair. Shedding is part of the hair growth process; a hair grows for several years (anagen phase), then stops growing for a few weeks (telogen phase), then a new hair grows, pushing the old one out. The problem with MBP isn't that you have a reduced number of follicles, its that the hairs they grow get progressively smaller and have shorter anagen phases until they're no longer cosmetically noticeable.
My (somewhat hypocritical, since I do it from time to time) advice is to stop counting the hairs you lose in a day. They're already gone anyway. The best way to evaluate your situation is to take photos every three months or so.
Stress can cause hair loss, but if you're losing it in the horshoe area, you've almost certainly got male pattern baldness, even if stress did speed things up somewhat.