Cats are highly territorial and they even mark their owners. Cats leave their scent on them by using scent glands which are located in their paw pads, lips, cheeks, forehead, and tail.
If your cat headbutts you and then bites you, it's probably hungry. However, this behavior may also mean your cat needs something else. Worry not, the cat will probably show you!
Cats are known for their rapid mood changes. So, one moment they enjoy your petting and the next moment they bite you, clearly wanting you to leave them alone.
Cats may rub against you and bite because they’re in pain. Unfortunately, they can't tell us that they're in pain, so, sometimes, you have to take your cat’s behavior seriously.