He wasn't really able to tear his eyes off of her, and it just made him feel like he could barely get any air through to his brain, like each breath hurt. He could faintly feel his hands start to get cold, his fingertips beginning to get a little numb from the cool weather. Even though he could hear her talking, all he could think of was the girl that he had spent a year with, the one that hadn't nearly loved him as much as he loved her.
He tried his best to shake the thoughts away, but every time he came back to now, looking at her, it was hard not to think back at all the emotions that had bombed him in that parallel world. A whole year of being human had definitely changed him, and he didn't think it was for the better - he wasn't as good at keeping his feelings in tact as he once remembered.
"It's alright..." he murmured out quietly, feeling a lump in his throat. He let his hands drop to his sides and he fisted at his clothing, needing some sort of distraction. "... Y-you know who I am?" he asked when he realized that she knew he wasn't the original Doctor.