Bisexual ???

Okay so I'm not sure if I'm bisexual or not. I've only talked to guys but if a friend comes over that is a girl I have the urge to be frisky with her. Idk if it's just because I'm horny or if I like girls too. I could never see myself in a relationship with a girly girl but maybe a girl that has a more manly look and attitude. Help!? Comment