Hi welcome to HCMForum. You fell down then pain has started. so the pain is secondary to the fall and related to it.
There could be a fracture
or a sprain
. I advise you to consult a local doctor for pain relief. Mean while i advise you
some diet recomendations as dont take potato other tubers tomato egg chicken and sea foods to bring down the
intensity of the pain. till you are at home. wishing for a quick recovery.