2-3 days seems a little soon to be doubting the legitimacy of anything. You really haven’t even scratched the surface of the diet.
Brain fog is also a symptom of die-off. Your CANDIDA is craving carbs.
I really can’t afford to lose too much weight either so I supplement with things like coconut oil. Raw extra virgin coconut oil gives me a burst of energy before workouts. Avocados are great too. Make some olive oil salad dressing!
I’m 5 weeks along and some days I have brain fog and some I don’t just depends on my body, supplement cycle when and what I ate etc.
Give it some time and your body will not only adjust but will thank you.