For me, I usually have a yeast reaction about a week after a round of chelating. It lasts for about a day and it has become less and less as I've continued chelating. It's possible that this is part of what you're feeling.
Perhaps you should stop the anti-fungal for a while and see how you feel. If metals are the root cause of your trouble, then chelation should help you feel better over time and the anti-fungal may not be strictly necessary.
I would also be patient. Chelating can take a long time, especially if you were exposed to a lot of metals.
After a few years of chelating, I don't have very serious yeast reactions any more. That happened without using an anti-fungal (except on rare occasions).