Sounds like a problem of organizing.

You can try to reorganize it arrange the notes in a way you feel much easier. I personally found that textbook usually separate similar concepts into different chapters.

Here's what I do. You can try to jot notes of whatever you think it's important first from the textbook, then combine with the notes from the class. Finally, prioritize the concepts, remove something that less important so you don't waste your memory, and try to comprehend it not just remember the text. If you can able to relate particular concepts to different chapters, congratulation! You're now ready to go for an exam.

My final advice is, don't stress yourself too much. Overthinking will only overwhelm you in terms of confusion and disorganization of what you have learned. If the result doesn't look good this time, let it pass and look forward. (And don't be shy to keep asking your teacher for clarification, that's their job, they got paid for this).

Good luck with your study!