Twig, I think you are right. The last fresh blood sign I found ended in the thicket. I have searched that thicket over and over and found no fresh sign. The deer is either dead somewhere in that thicket or is still alive and stopped bleeding. I'm starting to think it has survived.
I still think I may have hit a lung because I ended up finding some pinkish blood and blood with bubbles in it. I am going to let the area sit for 2 days and see if the deer returns. "The field" I shot it in has a food plot. I have killed deer before in this area and the deer always return. If the deer returns, then I am going to start hunting it again. If it doesn't return, then I will start looking for the body.