What Can Cause Swelling Of The Chin?

Two days ago I woke up with the right side of my chin swollen. In the middle of the swelling is a hard bump (pimple like, but no head). I let it be, wasshed my face and such. The following day it was more painful and felt more swollen, but still no pimple head. The right side of my chin hurts bad, the are around the bump is tender to the touch. The bump itself is hard and hurts. I have never had a pimple hurt this bad before. Last night I put a hot corn bag on it two different times, it has seem to help with the swelling but it is still sore to the touch, the bump and area around it. Do you know what it could be?