If you know what to expect and have practiced the skills you'll need, I don't think you should worry about it. That's sometimes easier said than done. I was always a nervous wreck before taking the practical (hands-on) tests when I was going through EMT training. However, once I got started, I was so focused on putting the classroom training into practice, I was able to close my mind to the fact that I was being tested and there was someone there watching every move I made. Hopefully, you'll be able to do the same thing. Good luck!