Thanks PhysioAdvisor I spoke to my physiotherapist and he didn't give me much insight as to what it may be, he was working on my lower back putting pressure on places that were burning, he then put electricity on my back, same as all the other times I've seen him. I haven't run for 3 weeks since he told me not too. Since seeing him a few days ago my calf is worse, I couldn't sleep last night and I had no load bearing on my back! Don't know what to do.