I think most of your symptoms are die-off related and to reduce them you need to go slower and not be so aggressive in your treatment. I tell most forum members to plan on a 6-18 month recovery and this isn’t a sprint, but more of a marathon.
If you ever start to feel really crummy, the simplest thing you can do to feel better is to stop taking antifungals. Additionally, sometimes cheat items can reduce die-off such as rice, etc. (items that are slightly bad).
Additionally, spirulina is something that most forum members do not consume and this could be causing problems such as diarrhea, etc. I had an odwolla (mispell) superfood drink a few months ago and it gave me the runs for a few days. Take a break from the spirulina and then start it again when you feel better. If you feel bad again then you know what is causing the problems.
What billion count total per day are you consuming for probiotics per day? You could be taking too much or the wrong strain and this could affect your body negatively. HMF neuro/forte in comparison, could be much more gentle on the body.
There is a chance you have something that is similar to candida but not candida such as h.pylori, SIBO (small intestinal bacterial growth), parasites, strept., etc. There are a lot of things that have similar symptoms and so this protocol might benefit a different bacterial strain if you have SIBO or h.pylori, etc. For instance, the spirulina could be feeding the bad bacteria and then you are killing it with antifungals, and this would likely make you feel bad. Without proper testing you are sort of doing a crapshoot on solving your general health problems.
At the minimum it sounds like you have a inflammation problem and you need to reduce the inflammation. Taking anti-inflammatory supplements such as fermented cod liver oil or anti-inflammatory foods such as salmon, broccoli, spinach, pumpkin, etc. could reduce the headaches, stomach discomfort, etc.