My cat has started laying with me constantly over the past few months. she didn't used to do this. could i be sick? i know cats can sense changes.

I don't think: behavior from your cat is a reliable way to determine if you are well or ill. If you are feeling fine, energetic, positive, then I would surmise you are well. If you are having some troubling symptoms or signs, or something has changed, consider a doctor visit. I believe your cat's behavior is more about your cat's well-being than yours. Consider whether she may be ill or she just enjoys you!

Dr. Cat.: At the risk of sounding sarcastic, which is not my intention, we wouldn't know if you were truly sick with an illness unless your cat had a medical degree. You're right in that some animals can sense disease, it seems. If you're not feeling well, or if you're genuinely concerned, see your doctor for a thorough evaluation. You just never know, truly.