Nausea for 3 weeks?

Hi ladies. So I've been feeling really sick and nauseas for 3 weeks now. It started on the first day of my last period (Jan. 14). There is a bug going around, but everyone in my household who got it didnt feel nauseas. I recently had my hormones checked and I'm not pregnant and everything looks good there. I have been out of the multivitamin I've been taking for a while, but this started even before then. I gag at the simplest of things that are gross. Idk what it is! Any ideas? I dont want to google it because I would probably get results like "It's CANCER". And I dont wanna freak myself out. So what are some more minor issues it could be?