A couple of weeks ago I started with one sided back pain and then groin pain. This then spread across the whole of the front and felt like period pain. I don't have periods as on implant so went to Drs who said it was probably a flare up of my endometriosis. She prescribed mefenic acid which takes the edge off the pain. It quickly settled back to one sided pain which is in back and groin area extending up to c section scar. Went back to Drs a couple of days ago as no change and she said she couldn't identify anything acutely wrong, no masses, no increase in pain when she prodded and poked everything, no temp etc. she has referred for an ultrasound to double check everything but I am beginning to wonder if it is back related. I have had sciatica type symptoms before, one sided lower back pain radiating down buttock but never into groin. I have also noticed that if I bring my knees up to my chest and then extend my leg on that side there is a cond of clunk in my back/pelvis. Any thoughts?....