Born biual or not?

I know a lot of people say you're born gay, straight or bi and I agree to an extent but I also disagree. I'm 17 and I'm bi but haven't come out yet. A couple of weeks ago I started watching The L Word cos I read about it and it really appealed to me, but I remember when I was like 13/14 and whenever it was on and I saw a romantic scene, not neccessarily scene, between two women it genuinely grossed me out! I'd be like "ewww change the channel quick" and now I'm 100% and when I watch the show I don't think "oh wow thats hot" i think about how beautiful and romantic it is. So was I born bi even though the idea of two women or two men together used to grose me out?