Something about the way John's voice rasps in his ear, through the Sending stone, makes his stomach tighten. Like he can see what John's face must look like right now, what it would look like if he were here, staring at him like --

"Okay," he says aloud, working to ignore it, "yeah. And if -- if I'm still feeling okay this time tomorrow -- then it means I'm good, right? Means I didn't catch it?"