Can I exchange my black iphone 5s for a white one?

I've had a black iphone 5s with T-mobile since last october and only recently i decided I just don't like the black anymore and would much rather prefer the silver or gold… I've had it for a long time, but its in great condition i've used a case and screen protector since I got it. Do you know if they will let me exchange it for a gold or silver?

No they won't. It's been far too long. That would be like them basically throwing a new phone away. Would you want to pay for a returned phone?
Usually in the first 14 days you can return for any reason. That's it.

No, go trade with a school mate, better yet learn to not change your mind on things so quickly.

What planet do you live on where you think you can just trade a used one for a new one?