Do dogs have schizophrenia?

I recently bought a poodle puppy and he has been very good, quick to learn and affectionate. He sleeps fine and doesnt even whimper much at all. He knows to go to sleep when the lights go out and generally doesnt wake up till the morning. Suddenly yesterday night he wakes up from sleeping and starts to growl, snap and bark at us. I went to see what was wrong and he kept barking, yelping and backing away from me dragging his two hind legs with him. Everytime i tried to pat or comfort him he would do that. I couldnt tell if he was being aggressive or scared or in pain. Though looking at him was heartbreaking because to me he looked so scared. Finally i just went and picked him up and held him and suddenly everything went back to normal. Please help if you know why he became like that or what is causing him to become like that. Thanks