"I can do that." If he can stay alert on guard duty, he can stay awake for Poe bringing him something to eat. Besides, it looks like BB-8 is staying to keep him company, happily chirping at him (he thinks it's happily, anyway). He really should start to learn the droid's language.

"Yeah, I'm glad you're okay too, BB-8. And Poe's right, isn't he? Rey's okay?" And even he knows how to interpret a nod from the droid, so Finn is grinning when Poe gets back. He still looks tired, but he's definitely awake.