A Sharp Pain On My Left Side Of Chest. Like

A sharp pain on my left side of chest. Like doing the pledge of allegiance. The sharp pain will last a few seconds and happens off and one all day. Sometimes worse then others. It's like a sharp stabbing pain
I've had some headache off and one somedays my clothes fit just fine and by the end of the day they are tight. Somedays I could be walking or just standing and get light headed.