I have suddenly began experiencing severe paint in my larger joints or muscles. It comes on suddenly, last for 6 to 18 hours and disappears...from that joint. But it is moving around - first the R. knee, then the right wrist, then left shoulder, elbow and wrist, now R elbow. The neck has a steady, never ending pain. Any ideas what is causing this? I am a 64 y.o. male, generally good health, tho 30 lbs overweight.