Chest and back pains

 I have been getting shooting pains in my chest for over a year now and have been told its so many different things but i cant seem to get an answer as to what it is, a few months back i then woke up one morning with an awful back pain that felt like i couldnt breath properly and my back was mega tight. I went to the docs and they think the two things are related even though being different paiins and sent me for a chest xray to check my ribs and stuff were ok. That came back fine so i need to go back to the docs again, i am on tabs for the pain but they dont work, my shooting pains have been worse than ever this week getting them several times a day and they literally make me scream in agony from the shock of pain shooting through my chest. I was just wondering if any one else had experienced anything like this as i cannot seem to get an answer out of anyone and its starting to worry me.

I dont think mine are triggered through stress, i am just worried as doctors keep telling me loadsa different things and no one can seem to tell me what it is lol