yes, the swelling will subside. But for any reason, if it does not , go see your doctor. It doesn't sound like an unusual injury- as you might imagine, that kind of misdirection happens all the time-- still, why not see a professional- no one can diagnose an injury correctly on line- they need to see you !
Your penis should be fine. Slight bruisng is no sign of severe injury. The tenderness should subside in a few days. It may take a little longer for the bruising to completey dissapear. If you are still concerned in a couple of weeks, call your dr. They can do ultrasound on it to ensure that nothing is 'broken'. You'll be okay.