I recently noticed a hard knot between my breasts at the bottom of my sternum. I also have pain in my left upper back and sometimes down into my lower left abdomen. It is sometimes tender to the touch, but not always. I don't lose sleep over it, food doesn't bother it, just the aches and pains in my upper left back and shoulder, sometimes on my left side. It doesn't hurt constantly and Ibuprofen helps. Any suggestions?
Any hard knots that develop on the body should be seen by a doctor. Not to scare you too much--but just enough--bad things like rheumatological disease and even cancer are associated with hard lumps that do not go away.