That's what fibro is all about! I did absolutely nothing to feel like I do today...like I was dragged down a gravel road by a rope on the back of a Jeep. Three weeks ago I climbed a mountain with my family and didn't feel this bad. I can walk into a store feeling completely fine and within ten minutes have to sit down somewhere. I don't get it either. If you have had all the usual tests ruling out everything else then acceptance is the only answer. I know it's frustrating and so many of us have had to give up our passions. I applaud you for still continuing to run despite the pain. It is so easy to just sit in a chair and give in to it.