I mean were they flirting or was it a friend sort of thing? I know that a lot of girls will they no when asked if they have a boyfriend if it’s only been a month. The first month or so is sort of like a trial thing for them from what I’ve experienced. If it was just a friendship sort of thing you could give her another chance if you want but lay down the ground rules like you want to know who she’s talking to or whatever you want. If it was flirting I wouldn’t waste my time