Nursing school is tough, hand in there, the reward will be so awesome when you finish.
Some things that got me through nursing school and study tips:
1. pre read chapters before going to class. In class write down all things the instructor mentions specifically about diseases/disorders. Highlight, post it/pagemark important charts.
2. record lectures and listen to them over and over again, driving, cooking, before bed, in the shower. i also recorded myself saying my own notes in my own words and listened to those constantly.
3. Don't over think tests. Go with your gut instinct. I always take my tests and go through the test and be sure of my answers before putting them on my scantron, if i didn't feel good about my answer i would circle the number and move on. I only revisited the ones i was unsure about and hardly changed answers unless i knew for certain i needed to change it.
4. Star to try to make connections between clinical and theory. Think of patients you treated with the diseases and think of them when answering questions and always think of rationales of why.
5. nursing tests aren't usually straightforward, so don't just memorize things. Get the whole picture of the disease and its effects on a person. Make sure you have a solid foundation of basic anat/physio so you can understand the effects of the disease on the various organs and person as a whole.
6. I always found it best for my learning style to re-write notes, like you said into personal study guides. Taking notes from the books, lectures, and other resources and putting them together to make individualized study guides and reviewing them and knowing them like the back of your hand.
7. commit, it sounds as though you have studied hard and put the effort in. Keep on working hard and using a few different techniques will get you where you need to be. Use your resources, does your school have a lab? Nursing tutors? Computer programs? Do your instructors offer tutoring sessions? Use all resources available to you!
Best of luck, keep studying and working hard. Its not easy but its all worth it. You can do it! Don't stress about the past tests, start studying for the next one!
One last thing, buy an nclex book
and practice answering those questions and reading the rationales for the answers. sometimes those get you thinking in a nursing mindset rather than just studying straightforward like other classes. Also, your book may have nclex style questions in the back, or online at the end of each chapter or system. Take a look at those, answer them and review. The rationales or questions make look similar to those the instructor will be asking.