If I only have one crooked tooth?!

retainers are ideally for after you get braces.. they are only there to "retain" the work done by the braces.. regardless of what your dentist says..

age is a factor though.. if the crooked tooth is primary, baby teeth, then you'll just have to wait for it to grow out..

if its on a permanent tooth, adult teeth, then braces with single brackets can be recommended.. but its slightly crooked then maybe a strong retainer is okay..

I think so... because before when I was visiting my dentist for my braces I saw somebody with only one bracket attached on one of his tooth and a wire around the teeth like retainer. But still depends on how old are you because the younger the more chances on you just getting the retainer.

Well... I think it depends on where the tooth is and your age. At adolescence, the face is changing and getting it's "shape" therefore your mouth shifts the teeth...But I think it's best to ask your dentist. :)

Perhaps a removable appliance could do it but you need to go see a dentist.

Pulling out