Have Horrific Pain In Back Left Side. Went Zip Lining

Have horrific pain in back left side. Went zip lining upside down and harness really seemed to hurt in lower back side with pressure while upside down. Tried to take some pressure off with pulling with arms but was painful in back. Wondering if pulled muscle or affected kidney area on left side. Hurts really bad when cough or sneeze. Ideas on what may be my reason for so much pain?