I would suspect the lungs were not hit buy the color of the blood described. A similar thing happened to one of my sons two yrs. ago. He shot from his treestand and the buck jumped traight up in the air and kicked before running off with his tail tucked and crouched close to the ground. There were 4 of us lookin' and we made sure this buck was not pushed. There was a lot of medium red blood to trail and when we kicked him out of his bed the blood sat in pools where he ws beeded. About 3 hrs. later and over a mile from the original shot, another son said he was close by because he could smell him. A moment later he saw him beeded in a small stream with no strength to go any further. He was put down there. This buck had been hit low with a gut shot. By the amount of blood he would not have survived the wound. Deer have a way of stopping bleeding when they hit water, almost miraculously. I don't believe this deer ran up and down the creek making it hard to track. I think your deer had the bleeding stopped as soon as she hit the water, just enough to hamper further tracking. My hunch is she was also gut shot, lost a lot of blood, eluded hunters looking for him and died somewhere else later.