Male pattern baldness at 17?!

[criswdsn]

So One day I cut my hair to a 2 to try out a new style. Looked pretty good everyone liked it. Then one day I look in the mirror and I notice at the top of my head (not the crown) but an inch behind my hairline and an inch before my vertex there was a small thinning patch. It wasn't that bad but I started freaking out.it was such a shock to me. My hairline was in perfect shape aside from my right temple I had slight thinning already. It was that way for at least 6 months! At the time I was trying a new diet called intermittent fasting and I did that for almost a year. Basically what you do is fast yourself all day and try to fit all your daily calories into a certain time window. (Google it for more info because I can't explain it that well) i was also finishing high school so I was very stressed out. And I was not eating healthy AT ALLL. I was foolishly replacing all healthy food with junk food because I figured calories were calories. yeah I'm pretty dumb . Anyway that went on for a while I finished high school and now I am 19 years old aNd My left side is still to this day untouched. my crown is SLIGHTLY thinning, the top of my head has thinned pretty badly and it's SUPER GREASY In that area only no where else. the top of my head shines but there is still hair there. And on top of that I have these weird lines of thinning hair that go from my crown and kind of connect to each temple, kind of like a "U" around my head if that makes sense. It really sucks. And it's only affecting the top and I'm 19. I have not experienced ANY shedding btw. At least not thatI've noticed because I keep my hair short. I also have a slight pain in my crown and at the top whenever they are touched. It also gets super itchy when I wear hats but it's been that way since I was 14. Soooo should I suck it up and take propecia while it's still thinning?? I saw my GP and he said it was just a little thinning nothing to be worried about and then I saw a dermatologist and he said it LOOKED like diffuse thinning and he sent me to another dermatologist like 70 miles away to see if it was MBP or something else because he didn't know and I have no time to drive out there and see him because I work a lot. My dad started thinning at like 35 or 40 and he's 65 and he's not even completely bald. He had a bad receding hairline though. And my grandparents were never completely bald. So why is my hairloss so aggressive?!?!?! HELP ME!!