Take some time to do something you enjoy! Remind yourself that the exam, and the score you get, are not the end all be all of your life. I'm taking the exam next Sunday and I'm also pretty scared, but know that we will get through this.
It helped me a lot to change my mindset about RC (in addition to drilling). Instead of hating RC and dreading the sections, I told myself "Wow, I'm so excited! RC is the best!" it sounds stupid, and feels a little silly, but I saw a big difference.