 [ Symptoms ] i am suffering pain on left side of my chest [ Disease ] hi left side chest pain can be caused by simple muscle strain or broken rib which then increase pain when you sit or sleep or cough splenomegaly can be cause of left side chest pain you should feel general fatigue if this is the case  are you alcoholic  there is the possibility of pneumonia plurrisy or plural effusion if you have breathing problem or respiratory problems hope you can give me more details to give you an exact diagnosis good luck