How Can Thumb Pain With Bruising Be Treated?

Jammed my thumb pretty bad 2 wks ago. When it happened I couldn't even turn the ignition on in my car for about a day. The pain woke me up that night so I took an aspirin and went back to sleep. Light bruising occurred a day or two later. Still hurts a bit now especially when playing volleyball. Any idea what it is and how to treat it?