I had the exact same symptoms....I was caring for my ill mother in law. (cancer) and I was helping her to the car one day, and she just went limp on me...........I grabbed her, pulled a muscle, so i thought.......About 5 months later I was still having soreness in my breast bone area..........doc xrayed it and said I had pulled tendons and ligaments...said it wouldn't get worse, but I waited so long...the bone cartilidge didn't heal correctly. He put me on Mobic and I can't hardly feel it anymore. I don't want to take Mobic for ever....he said take for a week, and then after that, just when I was doing yard work, working hard...but NOT to lift anything heavy!! So, maybe you ahve the same thing??