Going to steady Camilla is a reflex. He's in motion before he grasps what's wrong, which means that the spike of panic that comes with realization doesn't throw him off before he can be in place to support her with one practised arm. If it's something she's in a position to notice and think about later, it'll be obvious that he's done it before.

Jaune's not thinking about where he picked up any of his habits when he's staring at her bloody eye with wide ones of his own.

"I'm sorry," he says, urgently, parroting her words back to her with much more stressed intonation, "I didn't mean to - I should have known better - "

He almost says don't think about it, which would be a mistake for a host of reasons, starting with that being the most guaranteed way to make someone think about anything. More specific to the situation, this is the Camilla, and if there's one thing Jaune is willing to bet he already can guess about her it's that 'not thinking about Palamedes' isn't going to be an option now that it's been introduced.

Which means he might accidentally be responsible for scrambling her brain, which is just fantastic.

"I know him." Jaune nods, trying not to look too anxious and largely failing. "He, um. He mentioned you. Just...try not to press on anything that hurts? In your brain? It'll come back easier if you don't force it - do you want to sit down for a second? I think you should sit down for a second."