Getting Really Confused...

[confuseme]

So, for a period of time, I went through this phase where, male genitalia would turn me on, and I would only watch gay porn... but recently I've started to like this girl and we're boyfriend and girlfriend now... Since we have gotten together, I've started to become in love with normal porn, and now I get turned on by both girl and guy parts... but when she gives me a handjob, I can't seem to cum. I always ending up just having to masturbate myself, while we make out, but it still takes me a long time to cum, and I can only cum when I think about another dude's dick... I like this girl so much, and she gives me erections all the time, but why can't I cum when i'm with her? why can I only come when I think about another guys penis? Am I gay?

P.S. I can cum all the time when I watch normal porn and lesbian porn.

Please help me!