How to imrpove a 2-mile run time?

Im trying to max out my pt test and i need to run a 13 minute 2 mile im running aorund a 15 minute 2 mile. I get to the 1 mile mark around 7:30 but that mile back kills me. Any tips on how to imrpove on a 2 mile run and fast. I usually run about 2.5 miles 5 days out of the week for my running regiment but i dont usually time it