@Leed Thank you for your concern. After two more days everything gradually got back the normal. At least what I usually call "normal". :-) Seeing a doctor wouldn't have helped, I know it from my past experiences. There's no point in seeing a doctor when there's no high body temperature indicating fever, no infections causing you nausea and basically no biological trigger behind the symptoms.

@Wants2Fly What's the name of the book?