What exercises can I do to decrease my 2 mile run time?

I am getting very close to getting the run time I need to pass for Army PT test.I need to shave off about 40–50 seconds. I really want to pass my PT test before I ship to basic so I can be promoted. I passed the push up and sit ups as well as the online training. I know there are some people it was easy run , but I seem to struggle with it. When I first started running my 2 mile was 20:43,now couple months later last time I did it, was at 16:23. I try to push myself hard on the 2nd mile but I seem to run out of breathe and energy fast makes me mad…..Sometimes almost throw up.

I have about 25 days left, which is when I ship for basic.

What extra exercises can I do for my legs and core that will help me run faster and my endurance?

Also how many miles should I run a day? Should I run everyday?