Is it normal that i'm a straight guy who only watches gay porn?

You're bi curious not straight. I'm the same way, though the thought of gay sex outside the fantasy world is a huge turn on, so I'm either leaning more towards the gay side or you are fooling yourself. If hetro sex "doesn't do it for you", but gay porn is a turn on, then you probably are repressing your love of gay sex, as I did for oh so many years. I'm a lot older than you, but I think we both need to satisfy these repressed thoughts. A sexy woman is still a sexy woman to me, but as much as I've always wanted the pussy, I think I would choose the hard dick in my mouth at this point.

It always amuses me to see people saying things like "Is it normal for a straight guy to only do it with other men" or stupid crap like that. Just admit that you are at a bare minimum a female leaning bisexual.

Dude, you're not straight. You're bisexual. Because to be honest I am the same as you are. Watching male-female sex does not turn me on, but I am attracted to guys the most and only date guys, but watching "lesbian porn" makes me horny all the time.

Ever heard of the terms "bisexual" or "bi-curious"?
That describes your situation pretty well.
Also, gay porn is one of the best things humanity created.

I heard somewhere that gay porn only watches straight guys. Maybe it's a reciprocal agreement, like an exchange programme. Either way, I've got some gay porn outside and he says it's his turn to watch you.

You must be curious therefor your not totally straight. You just have to be honest with yourself. Obviously your not.

I like a guy sucking my cock and it was inspired from porn and then gay porn. Its all good.