Could be from your ears, too. Nausea is such a nag. I do the ginger thing a lot, any form. Also, there are acupressure points on the inside of your wrists. I guess yer not preggers, right? (That was a joke.) If it keeps up, get it checked out, living on rolaids gets old....... and masks symptoms..... ya know?
I've been nauseus most of my life from a zillion causes, it sucks. I hope you figure it out and loose it soon.