I took typing classes in high school and was never very good at it. I eventually gave up on trying touch typing and got quick at the hunt and peck method but in recent years I have found that I can type without looking at the keys or keeping my fingers on the home keys without really thinking about what keys to hit. Occasionally I have to glance at the keyboard to check where my fingers are, especially when using a different keyboard, but mostly I don’t think about it at all. So is it what they call muscle memory or has it just finally sunk into my subconscious where the keys are or is that essentially just the same thing?
If you didn’t learn something from a class there is no memory of it to “kick in” so to speak. Instead you have just taught yourself (perhaps building on something you did learn but didn’t recognize).
You spend too much time on the internet. 
I’m the same - never learned to touch type, but these days I can easily get 60wpm in those online typing tests without looking at the keys.