I have periodic stabbing pain in my upper right chest. Seems muscular. No swelling, no lumps, pressing doesn t cause it to recur. It comes and goes. No other symptoms... health seems perfect otherwise. I m 64, lost 20 pounds in last 90 days to get myself in better shape. Now pretty thin. 137 lbs, 5 6 , pulse normally 52. Very good shape. Your thoughts?