Suggest Treatment For Swollen Thumb And Blue/black Nail

Hi I slammed my thumb in a car door two days ago and it has been swollen since, and i have been in pain constantly for two days. My nail is turning blue/black, and I can move my thumb but I cannot bend it. every time i put my hand down, my thumb hurts more and more. Its very sensitive to touch and hurts when ice is placed on it. what should i do?