I've given up on figuring out "effect" versus "affect." Which is an embarrassing brain glitch for a writer.
Also, I've got a black hole in my brain where the math should be. This is very frustrating, because so many of the things that interest me (like quantum physics) requires a gift for math to truly understand.
You're not alone my friend. Black holes and brain erosion are what is SUPPOSED to happen when you try to figure out math of any kind.
I lost the last of my brain to "simple" (yeah, right) addition and subtraction well over thirty years ago.