Have a lump on forearm and mild pain after falling. xray had said no fracture. can x-ray be wrong?

Sometimes: Xrays are usually right but it the pain persists and you are concerned you could ask for a repeat 1 week after the injury. Lump on your arm could be a hematoma or contusion--these hurt! you can use pain reliever and ice if it is really bothering you.

It's : Not uncommon for an xray to be normal/negative in these cases. Further imaging (if needed) with ultrasound, ct, or MRI may provide additional information about the lump and pain.