If a couple is making love (sex) for the first time and the girl doesn't bleed, does that indicate she is wasn't a virgin?

No, not at all. The reason some people bleed for their first time is because their "cheery popped" or so its called.. I really don't know the proper name. But, if the girl is athletic or wears tampons, it could have popped on its own without her even realizing it. So just because a girl doesn't bleed her first time, it does not mean she's not a virgin.