Its fascinating. Its rare that I can have societal expectations of gender so strongly personified. Sorry OP, I don't want to come off as a dickhead, or cunthead... Whatever.
My snappy response would be, you have been surrounded by what CIS Het manly man is supposed to be, so much so that it may feel weird having any deviations from "it". Even though the societal expectations are weird.
For example:
I read many questions in the form of: "How do two women have sex. (I even googled it myself in my teenage years.) Why? Because:" sex is when a penis gets pushed into a hole. The one who has the penis is the man, the one who has the hole is the woman.
Two Men can have sex, because a man also has a hole. But then he is the woman. But, women only have two holes. They must need a strap on..."
Why is sex defined as something penetrating something else? Why? Its dumb, but it is the main focus when anybody in the "CIS Community" is talking about sex.
YOU CAN HAVE GAY SEX WITH A MAN WITHOUT ANAL, JUDY!
And the opposite is also true, a CIS man cannot like being anally penetrated. Anal penetration is "gay". Its dumb, hurtful to both gay and hetero people, and polices any sexual activity that may make your life more enjoyable.
I hope that you cherrish the little gem of weirdness that you found. That you come back to it, when you are ready to explore creative ways to have sex in your fantasy. And maybe, have a more fun and fulfilling love life as well.
I wish you all the best, random person on the internet.