My tiredness varies. If I have a really bad one off attack of full on dizziness, migraine headaches, muscle stiffness, nausea and vomiting it can last 10-20 hours. I can find after one of those it’s 4 or 5 days before the fatigue leaves me.
I can also have times where I feel like I’m not getting relief where I get milder smaller episodes over several days, I wake feeling ok and feel steadily worse during the day, and a few days of that that can also leave me fatigued.