I really missed up :(

I had a beta person, so when i loged on i put my "code" in. but i dont like my charcter so i deleted it. But now I cant use my code because i used it once. What do I do?

Huh? So you logged in, deleted your char, and you weren't able to log in again?

ya it said that i have already used my key, but i deleted my account. Now i cant make I new one cause i have already used my key. Edit. I only deleted my name and character, not my account. But every time a try to make a new charcter it say that my key has already been used.

I guess you'll need to contact the ArenaNet support for that one, i haven't got the game yet so i wouldn't know anything else to do.
Or, wait, do you have a pre-order or a normal package, i believe the pre-order people had the same problem as you until the pre-order servers went up, so maybe it'll al be fixed once the normal servers go up tomorrow.

if it was a BWE key it is only good for a single event not early access

I've got the same problem and I used the key I got yesterday.

Is your key a retail key, by any chance?

Yeah, turns out it is. I wonder where I would find the pre-order key... I don't see it anywhere in the box.