What Causes Swollen Knuckles And Fingers With White Scabs On Knuckles?

my knuckle on my middle finger is extremely painful. All my fingers on that hand are swollen and I have what looks to be a white-ish small scab on the knuckle. A little yellowish pus came out after I took a shower. Cold is the only thing that makes the pain stop. What is this? Should I be checked out by a doctor or is this normal or nothing to worry about?