I feel your pain brother!! I am just recovering from the same situation; hit water on a hard, steep turn in some foothills and ate gravel for 25 feet. It took 5 days for the gash on my left hip to stop bleeding, during which I was taking motrin by the gram.

If the pain doesn't cease, definitely see a doctor if you can, but don't freak out from people telling you that you have a concussion...most of the grade 1 & 2 concs we saw from IEDs in Iraq amounted to nothing but 24hrs of light duty then back to patrolling.