Is this natural for a bruise to do this?

So my sister and I were rough housing and I pinned her down, and in order to get out, so bit down on my thigh... Hard. So I go to look at it and I have a nice quarter size purple bruise with two red bite marks in the middle. Now, about an hour later, it itches like crazy, and its raised as well, like, swollen. It also hurts incredibly bad. I have on basketball shorts and I cant stand it when the shorts just barely even brush against it. It makes my entire leg ache Why is this bruise to painful, itchy, and raised? Ways to get rid of it?