i know cats can have mental disorders just like humans. my cat shaddow i love her to death but she is scared of me. She has a nervous disorder which makes her afraid of everything. She spent basically 5 years underthe bed only comming out at nite to feast and pee. My kitten paige i swear she has adhd. she is like a flying squirrel. My cat buddy has a issue with dogs. I adopted him at age 5 and will growl and his and carry on when our dog biggs is around. so probly ur cat has an issue with closed spaces or practically the car its self.