How do people who are child free by choice feel about not being able to get pregnant anyway?

I'm 25F and I'd say I'm 95% certain I don't want kids in my future. I'm also very early in my process of finding out whether I have endo- my mum never new she had endo until she was rushed into A&E with a ruptured endometrioma, (shes fine now) so she's understandably been pushing me to get tested too and I do have a lot of the same symptoms (currently awaiting a pelvic scan).

I'm also in a relationship with someone I'm certain I want to spend my life with. Before him, I only really half thought about kids and if asked would usually say I was pretty sure I didn't want any but also I was still young, I was very open to the idea that my mind might change once I got older. Now I'm with my partner, and he is pretty certain he doesn't want kids ever and I think as I'm getting older and picturing my future with him, I'm getting more certain I definitely dont want any kids.

But, something about approaching this whole endo journey has had my mind RACING about the possibility that I'm infertile. I can't even really pin down what I'm feeling, I've spoken very openly to my partner about it and he's been amazing but obviously he can only understand so far. I'm sure I don't want kids- even if I did, I actually think I'd rather be a Foster parent or adopt anyway because birth scares the sh*t out of me! So I'm really struggling to pinpoint what all these weird emotions I'm having around it all is. When I think about my choice not to have kids I feel relaxed and sure of myself. But when I think about how that choice was made for me anyway, I get really emotional and start welling up?

Would love to know anyone else's experiences no matter what they are- even if it was the opposite, I know some people who were relieved!

❤️