If you are signed up for a class at anything other than "Fundamental Level" but you have literally not touched a gun for SEVERAL MONTHS... this goes beyond a clue.
This is called a red flag.
Prerequisites are there as minimum requirements. They can never be all-encompassing, but if you cannot COMFORTABLY meet all course prerequisites at the beginning, you are engaging in self-delusion.
The above applies specifically to the classes that I teach, but I think applies across most of the spectrum.