THIS. Oh my goodness, this. Is exactly. How I feel.
Except that for me, it's not from people on Youtube. It's from my mom.
After so much time hearing her say "It's just a phase-- you're too young to know" or "It's mental illness, not a real, valid identity" or "You're just copying your friends and looking for attention-- this isn't really you," I start to wonder if she's right. I start wondering if maybe I AM brainwashing myself into doing this because I want the attention, or I'm making a mistake by coming to major conclusions when I'm so young. I know that's not the case, but sometimes it just startes to eat away at my mind and i can't stop second-guessing myself and everything I feel and do. It's like I'm brainwashing myself into thinking I'm brainwashing myself!
But then I think about it this way--
If I'm brainwashing myself into being transgender, I'm doing a darn good job of it, because it definitely feels pretty real to me. It feels real enough that I will be miserable if I try to deny that part of myself. And y'know what? If by some miniscule chance, someday down the lines, I decide I was wrong... I'll be no worse off than I am, now.
Ultimately, you're the one who has to live your life in your body. Therefore, you're the one who gets to make the final calls on what happens with that life and that body.