Slammed finger in car door?

On Friday I slammed my nail in a car door, which turned my nail complety blue. It was a constent pain so on Saturday I went to the doctor who poked a few holes in my nail to remove some of the blood. Yesturday night the pain was almost gone, but today there is a bump underneath my nail. My nail has stopped hurting but the bump is throbbing pain, does anyone know why this bump formed, what it is, and what I can do to relieve some of the pain?