Being nervous is normal. It is major surgery and a lot can go wrong. But most people don't get infections leading to amputation... They don't get PEs...they don't have major medical complications. If your surgeon and hospital has a good reputation then the probability of an uneventful surgery is on your side. Every time I started to freak myself out, I would remind myself that terrible things (like a major car accident) could happen at any time, but those things don't scare me out of living life, so possible complications shouldn't scare me out of surgery.