I have an indentation in my upper middle back. I've had it since I was 16, now 23, and do not recall any injury. It's never been painful unless pressure was applied to it. I had it X-rayed earlier this year and the doctor said it came back normal and said we don't need to worry about it but recently I have been having persistent sharp stabbing pain there especially when I take deep breaths. I can feel it in the front of my chest too. What can this be and where should I go from here?