What sort of male porn images are you collecting?
Are they guys with great bodies? Twinks, older guys or what?

One answer could be you're bi, another could be you just like looking at the male body. Maybe you look for inspiration, maybe you wish you had a body like the one you collected or maybe you "are" gay and just haven't experienced it yet...I dunno

Either way, if you have to ask...(???)

I'd say why don't you try dating a guy and see how that feels.
Can only find the answer in your self:-)