Two weeks ago, I was walking in my house, just walking, and I felt something 'explode' in my left mid-/lower back. I thought I pulled a muscle as I have had chronic back problems for 30 years and I know that sometimes it can be a delayed reaction when you get a pulled muscle. I took paracetamol, ibuprofen, used heat and the TENS machine. The pain seeped into my left side and spread to my groin area. This entire area is numb. Yesterday, my stomach became distended and hard and the pain is now focused in my left side, like a stitch from running (I assure you, there has been no exericise). I feel sick from the constant pain and I still have pain in my left, lower/mid back area where it started. If it was back pain one of the methods I tried would have sorted the problem. The only way to escape the pain is to sleep as it doesn't matter what I wear (I tried loose and tight clothes), it doesn't matter how I sit, or if I am still or active: the pain is the same and constant. I am a 55 year old woman and I have gone through menopause. I have had no symptoms prior to the exploding feeling I got in my back two weeks ago.