What is The Fluke?
1.
when one suffers symptoms of the flu(headache, stomach ache, etc.) but in reality it's not that at all, but rather a hang-over, morning sickness, food poisoning.
Susan: Wow, what was wrong with you last night. You sounded funky.
Lucy: Oh... I was feeling funky. Just a little head/stomach thing... not the flu... just "the fluke."
See