I just bought this textbook from a girl who was selling it online. I had some small talk and gave her the money. After that, she offered to help me with the material if I ever needed it (super difficult course). I said thanks and walked away. It didn't occur to me til later if she was either making a move or just being nice. I can't really tell. What do you guys think? Her Facebook profile says she's single if that helps. Should I pursue it?