The meeting with her old professor was a nice way to show how on edge she was and how intense her fear of failing her escape was. Especially because she didn't expect anyone to approach her, since she usually eats alone. Her fear made her somewhat paranoid to the point of her misjudgment of the danger of tge meeting with the professor. She started overreacting.

Does this explain it a bit better? Sorry I am still lacking in describing details in stories. 😅