What Causes Bruising On The Knuckles With Pain In Little Finger?

I hurt my hand 2 weeks ago hitting a wall. Xrays showed no fractures. i cant put any pressure on the outside of my hand and it still hurts my little finger when I spread my fingers. the outside 3 knuckles are still bruised as is the palm of my hand. if I press on the outside of my pinky knuckle it is very sore and it is difficult to completely straighten my little finger. what is wrong with my hand?