You have quite a long post, and I just woke up from very little sleep, and your post should get more then some grooty morning response, so I'll extend this post later, but I figured I should post something now, because I partly identify with this (except for the, I'm attracted to my birth sex, but trans people's orientations are really varied. I know a guy (FtM) who is totally only into guys)

Trans basically covers anyone who transcends their birth gender. This can be to the opposite gender, or something else, such as a mix of gender, both genders, no gender, and so forth. Though you sound pretty sure you are male.

We can't tell you for sure, and as far as I can tell, a lot of us arent always completely sure. Its a process that you need to go through. Perhaps consider presenting as male, or getting select friends to use male pronouns, and see how that makes you feel?

If you are still working out your gender, working out your sexuality will be slightly harder. Not all, but quite a few of the people I know who have come out as T, have over that process somewhat changed their sexuality. That being said, others, like the one only into boys, have always known I wouldnt rush into labelling this if you arent ready. If you like a guy, go with him, if you like a girl, go with her. If you need to label, do you think you like women in anyway more then friends? If not, why do you think you might identify as bi?