What should I do if I have a broken wrist?

See an Ortho surgeon. If your wrist is broken you need to have it fixed by an orthopedic hand surgeon. They will get a x-ray and possibly special tests and either set the fracture with a cast or operate on it if necessary.
ER. Get to an er asap. Elevate the wrist above heart level and splint in a neutral posture. Ice.