Hand/Knuckle Injury?

[Ray]

Once upon a time, I had a bad habit for hitting doors when I got upset, usually due to basketball or girls, lol, when i would do it I would hit the door or surface wrong, and it would like, push my ring and pinky finger back further onto my hand. They always came back to the normal position and no further problems. Over a month ago, I hit a metal door repeatedly but this time I hit it straight and hit my middle knuckle on the door. It swelled up real big, and it's been real sensitive since then. If I hit anything with that knuckle it hurts real bad, and swells up to bigger than even when I hit that door over and over. It's really painful to apply a lot of pressure on it, and even if I hit something gently, and if it a soft object, it still hurts [i.e. a basketball in a playful manner.]
I was lying in bed with my girlfriend and she rolled over on it and just the weight on the knuckle hurt a lot, not callin her fat of course haha.
Any clue what I did to it???