Most Helpful Guy
It could make a big difference depending on how extreme the appearance is. Though, I believe that the majority of the time, the people going and getting boob jobs, nose jobs, or other plastic surgery don't actually have an issue but their insecurity lead them to take action.
Most Helpful Girl
Depends how severe your nose was before. If it's horrible, yeah. If not, you'll look better (assuming the surgery is successful) but no one will notice.