I used to have the same kind of fatigue. When it was at its worst, I couldn’t stay asleep for longer than an hour and a half–sometimes even an hour was a stretch. I’d wake up sweating with my heart pounding. I could never sleep past 3am. During the day I was too tired to do anything but too wired to sleep. I was a completely anxious zombie.
What helped me most was a lot of detox. The wake-ups are often caused by a toxic liver. An over-burdened liver cannot produce enough glycogen and so cannot keep the body functioning. To keep the body functional, the adrenals have to inject increasing amounts of cortisol (which wakes you up). Over time this wears out the adrenals. This is the body in survival mode.
I believe my liver and kidneys were totally bogged down in candida byproduct (this was before I started on the diet). Using NAC 3x/day, Alpha Lipoic Acid, milk thistle, dandelion and artichoke helped immensely. It also helped with my migraines. With the NAC it’s also important to take it with 100mg of vitamin C, selenium and vitamin E for it to be absorbed fully.
Within a month I went from sleeping an average of 3.5 hours per night to 6.5 and more than this I went from being completely useless in the day to being able to actually being able to hold down some work.
I don’t know what to say about your fatigue and the S. Boulardii specifically, but I’d say if you can notice a swing in the fatigue that quickly, the fatigue probably has more to do with your liver and kidneys being burdened by candida byproducts and you might just need to make sure you’re taking everything you can to get that junk out of your body.
Hope that helps.