It sounds like a hematoma which is blood under the skin that has pooled. This is due to the trauma of the bump and sinced you said you bumped it pretty hard this can be normal and most likely bruising will follow. I would monitor it for tonight and see if the swelling goes down and if not you may want to have it checked especially if it is very painful, but alot of times when you do bump areas of your body they do immediatly swell and turn color, but in most cases by morning the swelling will have gone down considerably, if not then I suggest that you be seen by your physician who can check to make sure nothing is broken or fractured. You should apply some ice to it in 2 minute intervals and this can help greatly with the swelling and take some Ibuprophen for the pain and swelling as well.
*Cheryl K* Please click the
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