What Is The Treatment For A Bruise In The Buttock?

Hi, I slipped and fell down a flight of narrow wooden steps (7) and i have major bruising the size of my whole hand on my left butt cheek. Right above my bruise close to my tailbone i have this huge swell that oddly enough isn't bruised at all! It itches from time to time but I cant seem to itch it because the itch seems to be underneath the swelling and is getting to be real uncomfortable at times. It's been a week now since the incident and I can tell the bruise is starting to heal from purple to yellowish green, but the part that is swollen seems to be getting worse! I took a hot shower and it looks more swollen than ever. Not to mention the butt spasms I get with it! lol Could this be serious or am I just freaking out?