Been talking to this girl on the phone for about a week?

well ive been talking to this girl for about a week and tonighte she said we were friends now this girl has said I was hott she calls me more than I call her and when we talk the conversation usually last 2-4 hours. Shes always flirting with me too should I just keep going and try to get her becuase she could just be playing hard to get or something or should I just say *** her.