Silence. He's drifting, a bit, and when he realizes it - when the familiarity of not-quite-dozing, recognizing sounds without registering them sinks in - he bolts awake again with a flash of pure terror.

Steve blinks at her. He feels the way he used to, like the bottom of his stomach dipped into one knee and got stuck there. Weak, breathless - nothing he thought he'd feel again.

"Don't let me sleep." Deep breath. He hauls himself completely upright, letting that take before he tries to slide his feet over the edge of the bed. "I think I've done enough of that."