People are already telling you that eighteen is not too old to learn programming. And they are correct. People start at forty and fifty. I have a different point to make. There will always be someone smarter than you. Someone who started younger, learned faster, accomplished more. They're smarter than you are now, and they'll probably always be smarter than you. Just get used to that as quickly as possible and move o…
That aside, I didn't even go to college until I was 26 and it was for Biochemistry. That was too hard for my weak little brain, so I switched to CS (which wasn't much easier tbh, but it was a bit, for me at least).
I graduated when I was nearing 31, and at that point had only been programming seriously (internship) for a year.
I'm not that great still, but only been out of college since early 2009, but at least posts like this give me hope that I can be more than passable.