Can a dog get a concussion?
I've been keeping an eye on Ryu all night long, he seems fine, not acting different, no double vision, can concentrate, everything, checked his mouth, his head, front legs, no pain when I press on them or move them.

Last night, while I was sitting on the deck outside, he was playing in the back yard, there is a retaining wall... He normally doesn't do anything near the wall and he decided to take a flying leap off it, and smashed side of his head first onto the ground. For a minute he wouldn't get up... Then he got up, came to me, I checked him out, he seemed fine, he's eating, drinking, playing, I kept an eye on him all last night, didn't get much sleep.. and he still seems his normal self this morning.
I felt horrible because I was across the other end of the yard sitting watching them. It made me feel like I should have been there beside them while they were playing with each other (ryu and owen that is)