Why do a person avoid eye contact 😅

I had this recently happen to me when I went to talk to the a coworker that I liked her and she told me like me too, but I’m unsure why she said after it she not interested in anything else at the moment even mean feels like she just keep me on the a her list of guy. After that night she was still talking to me then like a week later totally like kept avoiding eye contact with me. She is suppose I’m have magic mind reading power to know what happen 😄.