How do I know if a sudden change in my cat’s behavior is a problem?

Sometimes it's difficult to know if it is a problem. That's why I recommend checking with the veterinarian because, again, you could see a cat straining to urinate that you might not think is a problem that could mean that the cat is blocked, which is a serious medical issue. Again, these issues can be caused by stress, so I would say any time a cat has a change in normal behavior lasting for more than 12 to 24 hours, it's imperative to contact your vet.

A change is probably the most important thing to me. That is when I would be first investigating the situation. The rest of it may be simply a conversation that you have with your veterinarian to really determine if this is a behavior that is occurring out of context, considered abnormal, or is it just a normal feline typical behavior?