I had a horrible infection in my leg...?

About February of last year, I had a motorcycle accident that resulted in an amputation of my left leg. The original amputation was below the knee, and about 5 months after the operation, I went in for another surgery to get some hardware in my knee removed. I then started feeling sick all the time and could not even function well. The leg felt like it was on fire, and was hurting me even when I wasn't moving my knee. At first I dismissed it as just pain and symptoms after the surgery, but after two months I went back to the doctor and told him there had to be something wrong... long story short over the next few months I had to keep going back to the hospital, and the doctor kept dismissing that there was a problem, even when the area was swollen the size of a softball. It is now March, over a year after the original accident/amputation, and I've just gotten back home from my 2nd amputation... I was so sick of the pain that I decided it would be better to cut off what hurt...