I've been there before. Panicking in the bathroom, wishing it wasn't true.
It's a hard question to try to answer because nothing I say is going to make you feel magically better. If you're already sick then more than likely it's going to continue to some extent. But learning what works best for you and fighting it everyday could mean the difference between hospitalization and infection, or staying home.
If you haven't done it already, I highly suggest you get a Doctor's appointment, the soonest available.
Ask for medication and start taking it round the clock right away. If you haven't gotten sick yet, you could just have it on hand until it starts. For some people it's violent from the start. Keeping yourself out of a bad cycle of dehydration and vomiting and not eating is the overall goal.
Medication to ask about:
Zofran: (prescription) (ondansetron) Anti-emetic (it helps control the vomiting)
Unisom: (Over the counter) (doxylamine) anti-histamine (helps control the nausea)