Is it normal that i lost part of my finger from a ferret bite?

It has been about two weeks since the doctors finally decided that I had to lose the top portion of my index finger from a rapidly spreading infection which was caused by a bite from my friends house ferret. The bite was not even that savage. I caught the ferret off guard and he did that weird dancing thing ferrets do and he bit directly through my finger nail and just about to the bone. I didn't get mad and cleaned the bite right away afterwards. I thought it would be fine. I was wrong. It only took about four days for the tip of my finger to become grossly infected. By the time I showed the doctor it was turning blackish and numb at the tip and he said it was too late to save the whole finger. I lost part of my finger to a common ferret bite, is this even normal?