You're likely to get an opioid analgesic for after the procedure, but it is likely it won't be a rather strong one. I have heard of people just getting Ibuprofen 800's, but call up after you've had it done and say the pain is unbearable, can't sleep etc. you might get something extra, but ibuprofen or naproxen do work well. As for your fear, I would recommend benzos, but don't know about your history/tolerance with them. Do remember though, that there will be plenty of anaesthetics running through your system while you are having the procedure done, IV midazolam or barbs, maybe fentanyl, maybe propofol. Who knows. I would just tell myself it should be a chance for a nice nap induced by heavy duty hypnotics, and I'd forget about the procedure.