How do I know if I am bisexual or pansexual?

I have always been attracted to men but when I hit around 13 I developed strong feelings for another girl a couple years older than me and so far it's been the only serious relationship I've been in (despite the fact I was only 13/14 and it may sound ridiculous an naive I know that I loved her). When we were together she identified as a lesbian but was always very androgynous and I always liked the rather masculine feel she had about her however I found out a couple years later that she now identifies as a man and will be starting testosterone treatments in autumn. I am still attracted to other women (admittedly to a lesser extent than men) but I've always been very confused as to what to label myself (I don't like labels but it's handy to actually know what you are when you want to come out to your friends and family). I looked into pansexuality and from what I've heard it's basically where you are attracted to women, men, intersexed people, androgynes, transsexuals, genderless people, genderqueer folk and basically anyone else regardless of gender or sex. So on that list I am attracted to women, men, androgynes, ftm transexuals, genderless people and genderqueers. At least I think I am seeing as I haven't had much opportunity to go out and meet a lot of people that identify with these although in some cases I find the differences between them to be so minute that I don't count them as separate to each other, although I may just be ignorant. I am NOT attracted to intersexed people or mtf transexuals. Don't know why. Same reason why gay men aren't attracted to women I suppose. So I don't know if I can really be considered pansexual if in some cases gender does play a part in who I'm attracted to. Oh I'm now 18 by the way :)