I'm a 26 male and have never had sex with a male or female. Throughout my youth I was only attracted to women, but now I also find certain men attractive as well. I watch both straight and gay porn, but a lot of the time when I watch straight porn I imagine myself as the woman. With gay porn I imagine myself as the bottom usually. I don't think that I'm transgendered, but honestly a lot of the time I think about how I would like to be a woman.
It's sounds like you may be bisexual and gender fluid. Look at these labels and see if you think you fit under them, but please realize you don't need them Unless they make you feel more comfortable. Also sexuality and gender can be quite fluid. Hope this helps!