Confused about my sexuality

Ever since i could remember I've alway been attracted to guys. Had boyfriends here and there and am currently in a long term relationship with a guy. I know that I love him and see a future with him. Sex is great. But I think I might be attracted to girls as well. Since sixth grade (earliest I can remember) I've caught myself checking out other girls but didn't pay any mind to it really. When I comes to preferences on porn and turning myself on, I alway find myself in the lesbian category. But here's the thing I've never actually been with a girl before. I don't know if I'm just curious or bisexual? Just looking for thought and bit of how you felt when you figured out your sexuality.