I recommend that you go see your doctor
. It could be that you have some soft tissue damage due to the trauma of the bump that is causing you pain. This would be similar to the pain that you have with a bruise
but is probably too deep to be visible. You could even have some bruising (which is just damage to the tissue causing blood to leak into the soft tissue) that is not visible since there is more tissue. You can have pain in the area if you damaged the bone as well - this could just be some bruising or superficial damage to the bone which would cause pain that will improve slowly over the next couple days. A fracture
of the bone is always possible though this really depends on your age, your bone strength, and how hard you hit the area. If you hit yourself really hard it is possible that you fractured your pubic bone. This would cause pain that doesn't really improve and could also cause instability or difficulty walking. Again, I would recommend that you go see your doctor to have the area examined and to make sure there is no instability of the pelvis; this is especially important to do if you have symptoms like difficulty urinating or having bowel movements, if you see swelling in your abdomen, or if you start passing blood.