Youll be good man. The painkillers are intense and shut down anything too serious. Ive had a femur repair with 6 screws and a titanium plate put in, 2 screws in a wrist, another surgery to yank the plate and screws off the femur, brain surgery. Painful crap man. Its nerve wracking going in, but you come out, you recover, and its not that bad. If your nervous about the dangers of anesthetics, dont be. That shit is so good the chance of any serious complications is like .0001 percent. Best of luck with the surgery, dont let it bug you too much, ACL repairs are fairly routine for an ortho surgeon and im sure it will all come out okay. And this may not make you feel better, but I wont lie the subsequent PT blows. There is just so much of it, and it seems like a never ending road, but it will. Best of luck bro.