Is my friend okay?

My friend the past two nights in a row has been acting kind of strange and I’m concerned. He’s come into my room after midnight these two nights seeming off just asking for a hug or lay with me for a minute. The reason I’m concerned is I’ve known him for close to 15 years now and he’s never done anything quite like this. When I ask if everything is okay and he can talk to me he either doesn’t respond or just says thanks and nothing else. Should I be concerned?