The German Shepherd dog gets killed quite early on in the movie and his head is thrown from the shed. You don’t seem him killed and the head doesn’t look at all real which is good in that respect.
The main character has a scar on his hand that reaches his wrist. He runs a knife blade over the scar, but does not cut. It would appear he was considering self harm. However, it is later revealed that his best friend has the same scar, from when they became "blood brothers".