It is very likely due to persistant pain that you may have suffered a fracture
. If you have associated symptoms such as swelling, loss of mobility or disfiguration, it further raises suspicion of a fracture.
The best thing to do would be to visit the A and E so that an X ray
can be taken and it may also require reduction by manipulation and immobilisation in a sling or a cast which may reduce your pain.
You may also be given other pain killers for your pain.