Rose watched him as he struggled with the shoe, he kept avoiding her question and it was really starting to get to her. "Ok, well just answer me this. Are you from my past or my future?" At least that should get her somewhere, and may explain his odd behavior.
After a few minutes Rose got down to the Doctor's level and helped him take off his shoes and handed it back to him, "better now?" she tossed the shoe between her hands. "Now you will get this back when you answer my question." She held the shoe in one hand doing her best to not give him an opportunity to steal it back.