This is going to sound horrible on my part, as I passed NCLEX-RN on the first try. But I think the first thing you should do is take a few days and do not do anything NCLEX related. Spend some time with your family and/or friends. Enjoy your pets (if you have them) and just decompress. There is no need to stress about it right now because if you did fail, there is nothing you can do to fix that at this point. In a few days you look at the requirements to re-apply for licensure in your state and you submit all the paperwork that's needed for your state/re-apply with PearsonVue and wait for the state to process everything and re-issue an ATT for you.
I (apparently I lived under a rock as a new grad) did not know about the PVT prior to or immediately following my taking the NCLEX. I tested on a Saturday afternoon because if I had waited for a weekday day slot I would have had to wait for 3+ weeks at that time. BIG mistake. So I got to stew about it for Saturday evening, all day Sunday and part of the day Monday - until I happened to check online with my BON (Ohio is the state I was originally licensed in), and my license was posted. In many ways NCLEX is a big test. But at the same time - the world will not end if you don't make it the first time. It may complicate things but it's a test. I'm not saying you shouldn't be upset - you are entitled to your feelings about the situation. So often, as nurses we put so much pressure on ourselves because we want everything to be perfect and we don't want to make mistakes. But the thing is - every situation is a learning opportunity. It certainly sounds as if you have spent a good deal of time preparing. Are you someone who has test anxiety? (I'm just saying this could be part of your problem - in my graduating class, one of the others in the top 5 of my class failed and she admits she was anxious and stressed and allowed herself to 'get stuck' by that stuff). I've found it is totally possible to 'over-prepare' and over think things (school taught me that). If you can - look at the situation for the day you took boards and determine where the wheels came off the wagon for you. Did you get stuck on a question you didn't like? Something you weren't comfortable with?
As for prep - I got my hands on as many prep books as I could (I lived in a major metropolitan area and the public library had a selection of current NCLEX books). Plus I can still use the library at my university/the state's inter-university library network. I wanted to see each author's perspective. There's valuable hints there. I studied some of the stuff from my review course (lab values, so on and so forth - things that could be memorized). I worked mostly out of the Pearson NCLEX RN prep book, the Incredibly Easy NCLEX RN book and the Kaplan NCLEX
RN book. I also had a Mosby book (required for school). The Kaplan book was awesome because I feel like the test taking strategies part / psychology of the test type stuff was the most helpful. I got to a point where I was getting most of my practice questions right. So I sat down and forced myself to do each book's practice test(s). Some of the books are hard cause they have the questions in one column and the answers in another, but I wanted to keep trucking on through doing at minimum 150 questions without stopping to check my accuracy - to help myself get used to not knowing if I was right or wrong. The Pearson book I had came with a CD that had a computer test mode that allowed you to do quizzes or a "mock" test mode - having to sit at a computer and do 150+ questions without the answers right away REALLY helped me I think. Obviously with the software you can review for correct answers at the end. Look at what you are getting right and what you are missing. And get in the habit of matching the words on the page/screen in the question to the answers. Even on my licensure exam - there were many questions I did not like the best of the answers ... I would do something different (still within my scope of practice but the best answer on the exam might not be my best answer - I had to learn to focus on my situation and options given).
After that - after studying and working on test taking strategies, I planned out my night before my exam. I got a 2pm slot (ugh). I planned to do dinner with my family and then go to a movie or putt putt /mini golf with some friends. I came home, watched some of one of my favorite TV shows on DVD on my computer and fell asleep. I set my alarm for around 11a to give time to leisurely get up, shower, get dressed, eat and go to the center (I was living at home and my parents house was about a 15 minute drive from one...). All through nursing school, I'd worked as a nursing assistant working part time 3rd shift - so I had gotten used to modifying my sleep schedule some... The extra time I had that morning, I took my dog for a walk and enjoyed how nice it was outside. I packed a snack and water, made sure I had everything and left. I knew if I did any questions the night before or day of and if by chance I got one or more wrong I would dwell on that / allow it to bother me instead of being positive because of the many many many questions I'd gotten right throughout studying. For me, part of it was the mental game with myself.
Hopefully some of this helps some (even if it's just taking some pressure off yourself). Things really will get better!