They're not always overly interested if they think it is 'self inflicted'.
That is scarily similar to what happened to me, from Hong Kong to Brisbane, just a few days ago.
I felt so ill I passed out within minutes of takeoff and when I came to, I was bathed in sweat, but I was told to just sit in my seat and recover. Alas I had been drinking earlier in the day (just two beers. really) so I believed the crew it was a sharp onset hangover.
Doctor confirmed with blood test its a virus, but sadly I've got home and infected a relation who is now in hospital with identical symptoms.
Don't ignore feeling ill before a flight. My bug went from feeling a bit ill to scary high temperatures causing unconsciousness over about an hour.
The real coincidence – I'd flown from PVG to pick up the HKG flight.