Back in February I had fallen down the stairs from the third step and landed on my right knee then flat on my face. at the time I had moderate pain in the middle of my back just above the pelvic area. The pain went away within the next two days. Six weeks ago I had a bad cold with a hacking cough. I coughed and felt a sharp pain in the same area on the left side of my back. The cold went away but I still have the sharp pain only when lying down or turning over in bed. The pain is not present any other time except when lying down. I have had chest xrays to check my ribs and lungs and everything came bcak normal.