I have upper back pain/neck pain. No injury occurred. The pain goes all the way through into my chest. It's been a few days and now it hurts when I swallow food. I can exercise (run, elliptical) with no problem. The pain is not consistent. It'll be steady, then just my back, then a wave of sharper pain in back and through to chest that only lasts a few seconds. I have no idea what this could be.