I want to be a girl…?

So. I want to be a girl, but I'm not sure if there's a place in the U.S. to get a sex change... I'm aware it mainly costs around $2000-$5000, But the only one I can find anywhere is either in Hong Kong, China or Bangkok, Thailand... Also. I'm not sure if I'm the right age at the moment... I'm 13, wouldn't I have to be at least 18 then do a year of some estrogen pill perscription or something?
lol at Adam. If I would be able to do this at 13-15 years old, I'm sure I wouldn't regret it; I've been planning for months about it... But I'm sure that's not enough... As said in the answers, I should wait 'till I'm older, although, I won't want a full MtF change (I'm pretty sure I'd want to keep my "stuff"), just the change where I grow long hair, actual breasts, My fingernails grow long enough as it is... ._. and other stuff like that...