It couldn't have been going too badly, because while York simmered, Tony lounged on one hand on the examination table with his tongue between his teeth, definitely not smiling. "Bad humour, more like. Or were you just getting to the funny part? My fault, I'm listening," he challenged, and even dutifully turned an ear to York, free hand raised to touch to his jaw to really focus, for about a fraction of a second. Any further and that charade might have come close to suggesting York had a joke ready. Immediately, Tony was looking away again, back down at the bottle with eyes wide as if in revelation. "Oh, right, 'mepivacaine hydrochloride', of course, that tells me exactly how much I can use before my heart shuts down," he enthused, then returned his impatient frown on York. "I'm not the pharmacist, that's not my area, she's not writing contraindications on these. Don't worry, I won't ask you for help again, I'll just trial and error it."