When I raise my left arm above my head and begin to stretch upwards I get a terrible pain just below my nipple and down an inch past the bottom of my rib cage. It is a line of burning pain about 6 inches long. It just appeared suddenly and it only hurts when i raise my arm. I can feel a little rope like thing inside and it's in a line. Like scar tissue or something. It doesn't hurt to breathe and it doesn't hurt with exercise. Only when I stretch my arm above my head. I did get hit in the chest with the end of a golf club the day or two before it started. That was just one spot however and there was no bruising.