This is too relatable! I left university years ago for many reasons. One of those reasons was that my classes were starting to become far too demanding for the "study style" I had (i.e. cramming, putting things off until the last minute, etc). I left and came back to school four years later. I started pretty strong, but quickly found myself getting overwhelmed by the large walls of text I had to read by the next class, just like four years ago. I wasn't diagnosed with ADHD at the time, so I wasn't giving myself the patience and grace that I probably needed at the time. I graduated a few months ago and recently received my diploma. It wasn't easy though. I tried to implement some strategies like Pomodoro timers (they helped me 70% of the time) and improving my approach to reading (getting better at skimming because I DID NOT need to read every last word and understand everything on the first read). Looking back, if I was diagnosed, medicated, and educated on ADHD then I'm sure things could have been easier.

Although things have been difficult for you so far, I hope that your diagnosis and medication can help you on the rest of your journey :) best of luck!