You should at least slow down, when you run out of breath try walking. Even if you do it at a fast pace. I had the same problem in high school (I even had the crabby gym teacher). As long as you are moving, he can't say you didn't put forth an effort. You may also want to talk to your doctor and let him know that this is happening. He will know what's best for you.
Well this is a symptom of asthma. But check with a doctor. I also have difficult breathing when playing football and basketball despite size of field and pitch.
My lungs get really stuffy and atimes have to fight for breathe. If thats the way you feel then please consult a doctor soonest....
You have to go to your mom immediately and get a note from your physician exempting you from this run. Your gym teachers should be fired immediately and criminally prosecuted. You have a simple problem you will undoubtedly outgrow, but with your symptoms you SHOULD NOT BE RUNNING. I want you to promise me to tell your mom and dad about this immediately and have them call the principal. You also require a good work-up from your family physician. If you don't have an insurance plan there are many clinics that will treat you reasonably. I want you to make a PROMISE to bring this to your mom's attention.