RE: Single lung shot
nc, Being able to tell the hit from blood shades and thickness along with hair type takes a lot of experience to be accurate. You may want to take a look at the Deer Shack and check out their posters. We have a few of them hanging at my camp. They are very realistic.
It sounds like you sure did your part, so keep your head up!
And yes, there certainly is the possibility that your deer survived.