My advice to you would be to RELAX!! you have done everything you could. If you studied appropriately and know your stuff, you will be fine. When I did my initial CFI, I was nervous and my nerves got the best of me. The more relaxed you are the more you are able to think and work your way to an answer. Being a little nervous is good, but just don't be overly nervous and everything will be fine. BEST OF LUCK!