This is going to sound like a smart-ass answer but....go to the doctor. Seriously - it's almost impossible to tell a soft tissue injury from a bone injury by yourself. You can try to test your range of motion but depending on your pain threshold, it still may not be possible to figure it out. As someone who has let serious injuries heal incorrectly, I know what kind of long term effects ignoring something like this can have...
If there is a real reason to believe that it may be broken rather than just "hurt" or "mildly sprained" then go get it checked out...
Good Luck!