So about a month ago this happened and now it is happening again. Almost 7 years ago now I was attacked and stabbed in the back puncturing a lung etc etc. So on the left side about halfway up my back I have a scar and recently around that area is really sore. I am hoping it's something to do with muscle strain or the cold weather as most seatches say but I am scared it could be more severe. I'm not worried enough to go to a doctor yet as I have no medical coverage and can't really afford it and it's not hindering me in anyways, though I will go eventually if things do not get better, I am just here looking for some piece of mind. The area feels as though it is bruised, though it is not, it seems slightly swollen but that could be because I keep touching it, sore to the touch. I can feel an absense of matter almost like a hole where the knife had gone in. I am having no trouble breathing or shortness of breathe and it rarely hurts during any kind of movement. But I can feel it there and there is slight pain to the touch. What could it be? What should I look for/do?

Have you tried any hot or cold compresses? Does the feeling change after a bath? But touching or rubbing the spot it can cause irritation and also inflammation. You know how the joke goes. So just try not to do anything with it and see if tylonol helps. If it gets worse in any way see a doctor right away.