A healthy level of anxiety/nervousness I believe is good. It means you plan to take it seriously. Keep alcohol out of the equation (you mentioned you recently relapsed). Even though you are brand new and probably a bit intimidated and scared, you'd be surprised how much a positive attitude and a genuine interest in learning as fast as you can helps. Your employer will notice that. Just imagine trying to do it with a hangover or going through withdrawal. yuk. You'll be fine. Hmm, do you get an employee discount at this spa?? That would be a nice reward down the road!