im a 15 yr old male and i have this problem with my lungs that really bothers me. the problem is whenever i breathe in deep, bend over, cough or sneeze the bottomg part of my lungs almost onto my stomach area gives this pain that feels like little knives stabbing at me and i do sports, active pretty much every day and ive had this before and usually went away after like 5 mins but ive had this for about an hour now and hasnt gone away. any ideas what it could b and how serious? if so what can b done to prevent it or to stop it when/if it does happen? please reply ASAP