The dr thought i broke my 5 th metatarsal but the x rays only showed a sprain. but it feels like it's broken. can i get a 2 nd opinion and new xrays?

Yes: You may want to wait a week or so after the initial injury to get a second set of x-rays. Sometimes small, nondisplaced fractures can be missed on initial x-rays. They can often be seen a week or two later, if present.

You could: You do not have to fracture a bone for it to hurt and be difficult to bear weight on. If pain, swelling, and difficulty walking do not improve in a week or so, followup with the doctor. Additional x-rays, or additional studies such as an MRI or bone scan might reveal an occult fracture or other bone/joint injury.

Often: A fracture if its a stress fracture won't show up on initial x-ray . Sometimes it takes 2 weeks to show. If you have a tuning fork, make it vibrate place it on the bone and if extremely painful it's likely a fracture.

5th MT fracture: Not all fractures will show up initially on xrays, especially subtle hairline injuries to the bone. Regardless, if the xray was normal then likely the injury will be treated the same way whether it is a sprain or a subtle undetected fracture. Let pain be your guide to activity and weight bearing. You can get a 2nd opinion, new xray, or even mri...But won't likely change the treatment.