I fell down the stairs 5 days ago and landed hard on my butt. ( it was the second to last step, carpeted). I got a welt the size of half of a baseball on my upper right butt cheek. The welt/bump has not gone away, the is a u shaped bruise around the bump. It's hurts when I sit down/ lay down, when I scratch or touch it there is no feeling on the bulge. What should I do, did I break something, should I go to my doctor?