Thanks i really needed that and i went to my doctor and they told me i was fine that there was nothing wrong so i'm going to get a new doctor and see if he tells me otherwise thanks
Bsmsl has great advice, see a doctor. No one on this site can tell you for sure what you have. You need to physically be checked out.
Your explanation is certainly plausible. but there are a lot of other possible explanations as well. You should have this checked out by your doctor. Exercis induced asthma would be the most likely problem, but the others need to be ruled out.
Feel better and take care of yourself.