Hi, I'm 17 too and I started stuttering when I was 11. I have no idea why (although I don't remember much about it, I don't know if it's related). The fact is that it's led me to isolate myself, so I know exactly how you feel, and if it's comforting to u I doubt people will think you're faking it people just don't really understand. They don't know what we go through when we can't get a word out. Tesxt to me if you want, I don't know anyone who stutters my age, haha.