My middle of the rib cage hurts when I do sudden movements. Moreover when I am sleeping if I suddenly turn to one side, it hurts exactly in the centre of rib cage (a very slightly to the right). Normally there is no sign but sudden movements cause it. Moreover it happens more during cough and cold. It has been there for about 1-2 weeks. Moreover I have a childhood problem of phlegm build up on my chest during cough and cold as a result my chest feels heavy, during such time my the conditions are more like sudden movement and breathing at the same time or just sudden movements hurt me in the middle of my chest. Is it serious? Moreover I used to lift weights a few months back but have stopped (not due to this reason, for some other reason)