How can you tell if your cat is experiencing stress or anxiety?

My cat Hammy started panting when we took him on a car ride the other day, that was extreme anxiety and I felt so bad about it

why do you only ask questions about cats

They will crap on the floor and not in their litter box.
They will hide.
They will not want to eat.
They will change their patterns of behaviour.

Ask it

Constant licking of fur not just for grooming, pacing etc

Some animals are wild. Some cats are.

Ah okay heres some advice, son. Boooooooo

Well, if you shove him up your behind to retrieve the gerbil you put up...nvm.