just gotta go for it. i was the same way before i learned 3s. i always psyched myself out, just couldn't do it. now, i throw threes first hit of the day.. just gotta force yourself to do it, and after that, it's sooooo much easier. it's all in your head bro.
now don't get me wrong, i'm not saying to go huck 10s n shit. that'll just get your broken. gotta build your way up, take one step at a time. just give'r