I HATE when I get one of those cases. One thing that sounds different, is that you say it's been more than 1 day? I have no business questioning you, but I have to say it sounds like the Novo Virus, which is like food poisoning, but lasts 2 or 3 days badly, then goes away then day or 2 after that. It's gone around a few times this year, and it's WORSE with more violent upset stomach than the flu. Most food poisoning I've had, lasts 4 or 5 hours of the worst upset stomach, then a few hours later I'm not sick anymore, but exhausted the next day.
What ever it is, get better soon, and go work out when you feel like it. No forced early back-to-gym!
Charles