About to turn 16, no clue what's going on...

[PlzHelp]

Hi, I'm about to turn 16 in a couple of months and I think I have diffuse thinning. I've never really noticed any shedding or hair fall and think that no more than 10 hair strands fall while I'm awake. My hair and appearance have always been one of the things that I have given great importance to. I've always had fine hair, apparently, but my father has a thick and full head of hair. My mother also has hair of texture somewhere in between thick and fine. Both of them have very densely packed heads of hair though. When I just turned 15, I had been growing my hair out for a while and kept flipping my part every now and then. When I would part my hair left to right there would be a line or spot kind of thing that formed and I assumed it was my cowlick, except I shouldn't have had a cowlick at that length. When I parted them the other way, no cowlick but my hairline seemed thinner and it generally didn't look as good to me. I shared this with my parents and they thought nothing of it, but took me to a dermatologist anyways cause I insisted. The dermatologist said nothing was wrong, though I suspect it was cause I am young and the guy didn't want to scare me. I asked another dermatologist and he gave the same answer, I'm assuming for the same reasons. Fast forward a few months and I'm extremely paranoid about my hair and my parents suggested cutting my hair a bit shorter because the longer hair might be weighing the hair on my crown down or some bs like that but at this point, I would listen to anything. Did that, cowlick/bald spot or whatever it is was still there, and over time I feel like it has gotten bigger. Btw I was on biotin ever since my first dermatologist visit up until cutting my hair short, it didn't seem to help much. Now, I've buzzed my head in order to reduce the breakage of hair and so I can oil them to promote healthy hair, and I'm starting to think that I'm diffuse thinking for sure. When I buzzed my hair everyone flipped out cause my hair looked good in general, but many people said the buzz cut looked good on me. Also, I have started clean bulking for athletic purposes and have always eaten healthy and consumed somewhat more than enough protein. Idk what to do if I'm thinning or am I even thinning and I miss my hair and I'm ****ing short and I'll never make it to d1 basketball and I'm just sad in general because of this shit now. Any help will be appreciated greatly...