Why would a girl you haven’t fucked yet tried to make you jealous, is it usually a shit test when this occurs?

I got 2 different examples

Say you tell her your interested and want to get to know her better and take her out for brunch, she’s like sure but the next day she posts a snap of a guy saying “the hottest guy on campus”.

Example 2 is when you know it’s not gonna go no where and you just ghost her, delete her contact info and social media. Then about a month later you see her pop up at the nightclub you work at and start to twerk, grind on my guy friends while trying to hate stare me at the same time. She’s not even 21, have no clue how she got in. We have really good carders.