"Oh." She didn't know him yet. Was this just fate laughing at him, dumping him in some stupid town and dangling all sorts of emotional baggage in front of him... for her own amusement? "Ah, you've not met me yet. Timelines," he told her, wiggling his fingers as if that explained it all.
"You'll meet me eventually. I hope. We'll have all sort of brilliant adventures. It'll be great, yeah," he explained, taking the stethoscope back from her and shoving it back into his pocket. At first, he didn't consider the possibility that she had already met him in a different body. "Quite soon, too. Sorry, this probably makes no sense," he shrugged. "Well, until we actually meet, just remember that you're fantastic. Absolutely fantastic," he said with a grin, not sure if he should leave... he couldn't risk telling her something she couldn't know yet, but at the same time he couldn't bring himself to just walk away. Not again.