my advice; get better
suggestions? train harder and actually run a damn race and not just "run" it like most highschool kids tend to do who cant tolerate pain fore more than a few seconds. as a 5:10 miler you should already have at least a 60 second quarter in you. you're probably just not going hard enough in the race. when you learn to actually run a race and give into any pain that comes with it, then you'll run fast. not everyone learns it, but if you do you get an understanding of what it means to actually "run".
actual advice? work on your footspeed and 200m speed. when in the race, go out HARD, and then hold on for dear life. its usually easiest to learn how to do this in a 4x400 where you're chasing someone down