I had a deviated septum for as long as I could remember. You don't always have to have an injury to cause it to become crooked. But I know that mine was a combination of genetics (apparently it can be hereditary?) and I was a gymnastics coach for a number of years and was constantly getting kicked in the face by little kids. I had the rhinoplasty and sinus endoscopy done twice to fix it and I can breathe so much better!
The surgery itself wasn't so bad because they knocked me out completely. It really depends on what else you are having done at the time. Because I had septoplasty/rhinoplasty along with endoscopy, I had a terrible experience with the pain the first 2 days afterwards. The worst part really was getting out all the packing, splints, and the gauze. After that, it wasn't so bad.
It did take awhile before I felt back to 100%, but I'm so glad that I had the operation done because I don't get near the amount of sinus infections that I used to get and I also can breathe so much better!
Hopefully things work out for ya!