It’s okay, just relax. Calm down, clear your head space, maybe get a juice box or something. You have two hours, think about this logically. It doesn’t need to be anything fancy, Worst case - you can always use the ol’ cliche ghost costume by cutting some eye holes into an old sheet, although your parents may not be too happy with you doing that.
Now, Deep breath!…exhale.
What are you going to do?