You're 20. Of course you don't want to have kids. Very few people at 20 want kids. I certainly didn't.
In fact, at 26, I was settled on being single for the rest of my life. I'm now 33, married, and have a 1 year old son. I laugh at my past self and understand how naive I was.
I'm not suggesting you'll be the same, just that you pay attention to the fact that you are seeing the world through the eyes of a 20 year old. :-)
You won't run into "the girl" though if you are standing still.
The problem is that the kind of girl who interests me intellectually and understands me (outside of my programming interests) is supremely rare.
I've mostly accepted that either chance will favor me and I'll run into the "girl", or I'll focus on my work. I don't really care.
It doesn't help that I refuse to have kids, that narrows down my options as well.