Dryly, "I'd really prefer if we don't." He just wanted to make sure his head isn't worse than it feels! It's fine!! There's no need to freeze him over something so minor, especially when it's already so chilly out and they're likely to be stuck here for at least a while longer while they puzzle out how to escape.

"But I don't know why it would have done that... was it something I said, maybe?"

Is it another one of those 'say nice things about the person you're trapped with' situation? Mysterious.