Animals get sick, hit by cars, beat up by other animals every day, all over the world. Not all injuries are imediately fatal. These are facts you know are true. Deep down inside, you know you did the right thing by not shooting her. In the days she has left she can teach her fawns allot of lessons in survival. Who knows? she may even survive the winter. I have seen many 3 legged deer make it more than a year after the injury.