"I'm a stick! I'm a stick! How am I supposed to catch my breakfast with you stomping around in the woods? Go away! Leave me alone!"
Probably a non-venomous eastern hognose.
Update: Our friend, Dr. Mickey Parker , suggests that this fellow may be a grey rat snake. After comparing photos of hognose and grey rat snakes, I believe he is right. The rat snakes tend to kink up when they get stressed. So do I.