Arm pain...............?

Ok, this happened yesterday when i was skiin. I do not remember how this injury occored but i do know that it occored in the terrain park, by lunch yesterday i could not use my left hand. I could not hold anything or wrap my left hand around anything. (I still cant) I also cannot bend my wrist up by myself but i can use my other hand to stretch it without pain but it can not by itself, also i can not let my hand hang to far down with out pain. But i do know that it's not broken, becouse i delt with thatt before.