What causes prolonged pain in the heart, lungs or ribs?

Sometimes i'll have a sharp achy pain that seems to be coming directly from behind my lower ribs, and sometimes pain will develop in my heart or lungs, and may sharply increase with deep breath or movement or when i smoke. i'm 19 hand have been a smoker of marijuana and cigarettes for about 4-5 years now, I had thought it might possibly be pleurisy due to the coughing up dark green, yellow and sometimes black stuff which been present months before the pain started.but im really not sure, due to the fact most of the other smokers i know also cough up a wonderful assortment of colors. i would have gone to the doctors much earlier but i have no i.d. or money for medication