Hi Cherie - I hear you on the greasy food. I had mild all day nausea (never peaked into vomiting) from 5 weeks through to 18-19 weeks. The only food that would ever 'cut' that nauseous feeling was deep fried items (!) preferably protein. That goes against every thing you read about what foods to steer clear of!
I found B6 helped and lots of small snacks throughout the day, as well as getting a rest as if I got too tired it was worse.
:-)