A strange bump on my wrist?

I have a strange bump on one of my wrists it extends only about 1/2 and inch farther off my right wrist than my left one. It does not hurt but is squishy and a week ago when I first noticed it it had a scratch mark on it. It is not itchy or anything I actualy completely forgot about it for a few days untill now. I know I should get it checked out just incase but until then could someone give me an idea of what it might be? thanks.