I'm guessing you're going for a rhinoplasty? You haven't actually said, but you mentioned your nose ...

Depends really, there's risks with any form of surgery, but go to a reputable surgeon and there really isn't much to worry about. I don't know what you're having done to your nose, but if it's augmentation with use of an implant I'm guessing there'll be risk of migration. There's all the general risks as well, such as nerve/arterial severing, disfigurement ... all really only having minor possibilities of it happening. My friend recently had her bridge reduced, no complications, no visible scarring and it's only been a week or so as far as I know.
I've not had any plastic surgery myself and I doubt anyone on here has, so it's best to ask people who are experienced! Visit the purse forums, they have a huge thread on rhinoplasty. People share their experiences, befores and afters and generally just discuss.