How to have more stamina while running? 10 easy pts?

Ok today at football practice we were in groups, people who wanted to be running back, q.bs ect. I was with the Linemen. Our goal was to run in 1:35 min around the track and i did it in 1:36 and when i was running like at midway point of the track it was really hard to breathe and felt like my legs were going to give up. And when we went up again, (about 10 min later) our goal was 1:50 and while i tried to run/jog my body couldnt take it anymore the more i pushed my self the worst it was. I ended up with 2:03 min. How can I build up more stamina? And if it matters im 15 5'6 and about 193 pounds