my dog was acting fine yesterday and playing with the dogs. when i came back to pick him up he was acting weird wants to sleep, doesnt want to play and he wont eat or drink anything. he has had a concussion before and he is acting alot like he did when it happened the first time, except he hasnt been throwing up. and i wasnt there yesterday to know what happened. i am worried because it is his second concussion and he is only 10 months old, he is a miniature Shih Tzu.