15 year old cat biting me in my sleep?

My brown tabby "skipper" is 15 years old. He runs around the house really fast like he's high. He's the best cat i've ever had, he snuggles on demand and sleeps all day. He's declawed aswell. For the past 3 nights he's woken me up several times nibbling on my face/top of my head. I don't mind it but I was just wondering why a 15 year old cat does that considering all I've read about is kittens. Does he think I'm his mother or something? Strange kitty kitty