When you have done all you can, stand. Just be. Release the need to control outcomes that are outside of you. Know that you have done your best and that whatever happens will help you. You will get your desire. You will get a great education so that you can improve. And/or you will get something different and likely better than you had thought, only you couldn’t see it before.
This is a very simple concept and one that will eliminate much if not all of your (dis)stress if you apply it consistently. It is simple, but it takes time and commitment to practicing it before it becomes second nature. We have been conditioned otherwise. We have been conditioned to keep pushing and pressing and trying to control everything. The wonderful news is that you really can control all you need to control, and practicing this teaches you how. To control your own thoughts and thus, your actions and behaviors, gives you the control that we all as humans seek. It gives you the life you seek as well.
It may seem hard to get started and you have likely heard this advice before but haven’t “done” it. I help my clients to apply the concepts not just learn them intellectually.