What Causes Swelling And Pain In Mid Back,groin And Knee Despite Taking Solumedrol?

Ok, I fell off small porch, 4 stairs, on 4/8/15, thought it was raining, but was sleet. Missed all stairs ended in driveway. Had significant swelling mid back above coccyx. I have been prescribed 3 doses of Solumedrol dose packs along with short term percocet 5/325 #20.I have a golfball size area now on my right lower back.I ended up in Urgent care last night, as I had such extreme R hip, groin along with bilateral inner knee pain.I was convinced I fractured my hip.Nothing done there, I did not want steroids, muscle relaxants Valium ect.I am sitting on a chair and now having to lean to the left as this area is uncomfortable.