Being nervous is a very normal part of this surgery. As a matter of fact, if you weren't nervous, that would be abnormal.....
But soon, it'll be behind you and you'll be recovering and looking forward to getting your life back.
I've had both generals and spinal anesthesia, and I will never again have GA if given the choice. I chose a spinal with deep sedation for my revision, and am so glad I did. With GA, I always had major problems with nausea; it took me, on average, 4 hours in the recovery room to be alert enough to be taken to my room, and during that time they always had to constantly tell me to breathe as the monitors went off constantly, meaning I wasn't breathing well enough. They had to give me masses of different anti-nausea meds before, during and after to keep me from non-stop vomiting, and so on. With the spinal, I woke right away, was totally alert and had no issues with breathing, nausea, or grogginess. I went to my room in about 20 minutes or so, and was fully awake and alert with no residual after effects from a general.
With the deep-sedation spinal, I chose to be totally out, which is the only way I would do any surgery, as there's no way I would ever want to wake during the surgery and see or hear any part of it. Mine was done right before the surgery, in the operating room, along with an epidural for pain control after (I can't take any narcotic pain meds do to my crazy body's reactions to them, so they have to use differing forms of pain control for me). I would say it was uncomfortable having them put in, but knowing what they were for made it easily bearable.
I also had a pain ball for almost a week after they removed the epidural on day 3 or 4, and that took care of any pain. The one I had was basically the same as the On-Q, just a different brand. I was very lucky that after I removed the pain ball I had no significant pain, but that's very unusual. Most people will continue to have pain for a while, and will be given prescriptions for pain meds. I'd spend some time with my OS asking what he does specifically for pain control, and what options you'll have.