I'm 15 year old female, and quite fit. Lately when I go for a run, within around 3minutes of running, I lose my breathe quite quickly, and begin to get a burning felling in my throat and lungs. I soon struggle to breathe, and alot of pain in my chest. From there I can't push myself to continue the run for on some accounts I have collapsed. So after i stop my run, i start to get a sharp pain around my heart and under my ribs on my left side, aswell as in my lungs. I get dizzy and still struggle to breathe. I would much like to know what is causing all this, so I can fix it, and get back to being fit and healthy soon!