Being kidnapped, being tied up and left in the woods, having her wrists and back bandaged...those Luna was more used to than the situation at that exact moment. Which, really, if she had had the perspective to see it, was actually quite the reverse of normal.
Were she anyone else, she would have likely shifted uncomfortably, but it was just not in her nature.
Luna was surprised when Andy called her beautiful. Obviously she was aware that she was not physically displeasing, her father still called her his 'pretty daughter.' It was just that...well, people summed her up by the beliefs she held that they considered odd, by the way she moved and spoke, and every once in a rare while by the fact that she had been at the Final Battle. Although that last one had only come up in very specific circumstances, and it had been long ago.
The world was what it was, beautiful and magical. And she was who she was, the witch had always found herself secure in who she was and what she believed in. Worrying about her physical appearance had never been an issue, especially as during her teen years, when that issue could crop up, she had been busy attempting to fight Death Eaters and survive. Helping Harry and the rest of the Golden Trio try to stop Voldemort.
Usually she was pretty good at guessing peoples' intentions, at understanding what they were doing and mostly why. "I am sorry," she apologized for the unusually bad leap of logic. "You would not," her agreement that he was not the type to make fun of her was immediate, instinctual and true. Somehow she knew that he would not, and it surprised her to think that someone would not even think to tease her. At least not like she had thought he just had.