Okay - we all know the pain you are feeling is pressure due to inflammation AKA fingeritis....
One of the key this to do is ice and heat.
Ice on your finger and heat at the wrist. It works like a vacuum. The area around the inflammation contracts and the area below (viens take away to the heart) expands. The swelling will dissipate.
If the swelling does not subside by tomorrow my advice is to go to a health food place anf get Arnica tablets made into tissue salts. They instantly dissolve and work very effectively.
I am not a doctor but I played one in a elementary school play an few times.... Any questions feel free to ask. I hope you feel better.