I can't imagine walking into a class without knowing exactly what I was going to say and do with them
Don't worry, I did have that panic before I had taught that unit before. But when you are teaching the same thing all the time, I could just ad lib. That planning is a killer isn't it?
Horrible. Took so much time! But my students, unlike other math teacher's students, were able to do well on their exams without my having to curve the scores. The teachers who didn't prep, didn't make their exams carefully, would have entire classes not able to score above 40% on any exams. I am quite proud of how my students did, and it was because I worked so hard on crafting my classes, their homework, and their tests. As hard as they were, those were some of my good old days.
There's a reason to be proud! I loved teaching for those successes too. It was just far too much giving for me in the end, as you know. It just became not worth the huge, huge, huge effort you put in with no checks and balances for teacher's mental health. Don't even get me started.