text: Funny you should say that you hit it like a volleyball, I had this same injury from a volleyball. My diagnonsense,...in simple terms I bruised the bones, pinched a nerve (thus that lovely tingling sensation that will abate after a day or so), and broke a cluster of blood vessels, thus the resulting lump.  Do not fear, it will heal, but it will be mildly painful and aggravating for the next week or so depending on how fast you heal,...I found that putting an ace bandage on it worked fairly well to keep me from strainign it. \n\n  And as with most things like this, the injury will fade, but the embarrasment seldom does,...hope you had better luck then me and just hurt your arm,...because at the time of my injury I dived for the volleyball and my pants split straight up the back,...hehehe