What should you do if you don't do as well as you had expected to do?

If you don't do as well as you had expected, then you have to train harder. I don't mean to go the next day or even after the race and do a track workout or something difficult. The next day, do a 5-6 mile run at a good pace. Try doing longer distances for practices and while you are doing them, do some surges that will also help you with your speed. Be consistent and don't slack off. Doesn't matter how tired you feel, how many cramps you have, or if you can't feel your legs. You have to push yourself so your body can get used to the feeling and you can help your endurance and speed.