Yeah, if you wanna know what your cortisol levels are then the saliva test will be the most accurate. You can order one yourself from http://www.mymedlabs.com
Good, I'm glad that you're not eating/drinking sugar. I hope no more caffiene either. It sounds to me like you definitely have adrenal fatigue. I personally believe that how to go about fixing it depends entirely on how you got it to begin with.
It sounds like you are on the right track with the Candida diet. Even if you don't have Candida, Candida diets are generally good for folks with AF. Are you eating gluten? You might want to cut that out just to be safe. Salt in water is great. Good fats- great! Make sure to carry healthy snacks with you that are balanced- a little carb, protein and fat in each snack.
I recently posted a decriprion for someone as to what supps are generally helpful for people with AF and how to dose. Let me see if I can find it.