There are several things you can do to deal with nerves. You've only got two days so some of them may not work so well. And you're a teenager so herbal remedies will need to discussed with your parents.
1. Get all the fear and anxiety out of your system now. Imagine the worst possible scenario happening, allow all your fear and anxiety to boil up and out, and then get rid of it.
2. Free associate in a journal. Start writing whatever pops into your head about the competition. Keep writing until you've got nothing left to say about it. Dump it all onto paper. Once it's on paper you don't need to remember it, because it's all written down.
3. Exercise. You've probably got some extra adrenaline pumping through your body right now. Exercise can help siphon it off.
4. Crank up some elevating music. Whatever pumps you up and makes you feel good.
5. Valerian is an herbal supplement which can relieve anxiety. It also is a sleep aid, so you need to be cautious about taking it. And if you are under the age of 18, you need to discuss taking it with your parents. There might be a medical reason for you not to take it.
That's all I got.
Good luck.
