Does anyone else get intense pain suddenly in the middle of the upper arm or lower leg while resting and after no exertion? It feels as though I have been lifting an enurmous weight and really overused the muscle in my upper arm right now when in fact I'm just sitting with that arm resting while using the other arm. Generally it takes me by surprise and puzzles me, particularly as it is long lasting over maybe ten or fifteen minutes, sometimes longer. It can also feel as though the pain is coming from the bones themselves. as it is midway along them. Any suggestions would be greatly appreciated!