Religion has nothing to do with it. You felt that sense of wrongness because same-sex sexual relationships are wrong from a biological, procreative perspective. The shame and guilt you experienced afterward were reactions to what is fundamentally an unnatural act. Note I'm not engaging in an anti-gay diatribe here. I'm a near-absolutist when it comes to personal freedom so if men want to fuck other men to the point of anal prolapse and women want to fuck other women in sterile, dead-end relationships, then sure, have at. That's their business--again, within limits, with one of those limits being coerced societal acceptance of these behaviors as normal and right, something to be encouraged. It isn't normal. It isn't right.
I also believe in objective truth, which tells me most gay people aren't born that way. For example, I have an arts background, so I've encountered a large number of gay people in the course of my professional life. Some I consider friends. But get this: nearly every gay man I've known well has admitted to being sexually abused and psychologically manipulated as a child and I suspect the ones who didn't admit to it were. They've been groomed from an early age to overcome that natural repulsion to the act by evil pedophile faggots to think what was being done to them was perfectly natural.
Human beings are mammals. We breed sexually, male and female. This is biological fact. Any sexual behaviors counter to this are abnormal and--for the sake of the polis and the species--should be socially and culturally discouraged.