I don't talk to this girl very much, she used to be neutral to my presence, and then she randomly enjoyed my presence and would smile and laugh when I was around, often trying to joke around with me, I just ignored her when she did this, and now whenever I am around, her facial expressions and body language change, and it is visibly clear that she is pissed off by my presence, she will be completely chill, then if I walk by, her expressions change.
I was always neutral to her presence, and never cared about it, I barely talk to her or care for what she thinks of me, I'm just intrigued by the psychology of this. How does one get mad by someone's presence when you barely talk to them and have no bad blood.
I am high school senior, she is as well.
Can someone also explain the psychology behind this behaviour as well,