Have you tried Liquid melatonin for increasing your serotonin. Melatonin has been a huge help for me at times when my gut is upset or i'm feeling anxious at night. Seems like the melatonin seems to help calm the storm in my gut and helps to relax me-- So i can actually fall back asleep and not stare at the wall for 3 hours.
My indicator of how much candida is in the colon has been the fermentation "level" that goes on 9-14 hrs after you eat a meal(depending on your transit time)/ and your level of constipation. So if you ate a meal of "only" raw fruits and veggies in the evening and it made you feel like hell in the morning(excess fermentation) than you might be dealing with excess candida in the colon. Extreme constipation can be a sign that there is not enough flora in the colon generating beneficial acids to help push the bowels out.
Once the gut gets overtaken with candida it becomes very difficult to regain homeostasis. Did the Coconut oil protocol do you any good? Were you able to work up to 4-5 tablespoons a day? Completely avoiding sugar was a nightmare for me. It seemed to cause candida to go more pathogenic creating more damaging enzymes/inflammation.