In very close 3rd person limited, how subtle can emotional reactions be before readers miss them?

So, I'm writing in a very close, third person limited perspective. You know, narrator inside one character's head and perceptions, no omniscience, etc.

The protagonist, a low class scribe nicknamed the Penman, is occasionally called by his stripped and monosyllabic given name Tokk by superiors. This is meant to be humiliating and dehumanising, due to in-world lore reasons (lower class = simpler, shorter names).

Now, whenever this given name is dropped in conversation, I want to convey the little emotional hits of anger or shame without breaking the POV or using lines like He recoiled or The Penman felt humiliated.

For one specific scene, my current idea is to first establish his steady penmanship a few beats earlier, then let the name trigger a tiny involuntary slip (say, writing hand jerks slightly, ink smudges), followed by him calmly replacing the sheet and continuing as if nothing happened. This interruption of his one area of mastery/control should communicate the effect the name has on him.

All this, to pose the question to you guys: Does this kind of indirect, physical/sensory show-don't-tell approach land the emotional weight for you as a reader, or does it sometimes feel too subtle/distant? And, what other techniques do you use in tight close third to convey internal reactions without labeling emotions or stepping outside POV?