I haven't had any MS yet either and I am 9 weeks tomorrow, but yesterday in the middle of the (very crowded) grocery store I get a very strong wave of nausea. I was trying to figure out what to do because I don't think they have public restrooms there. I was terrified I was going to throw up in the middle of the aisle.
Before pregnancy I would get acid reflux induced nausea and tums usually help but of course I was out of them. Being a smaller store, they didn't have any either. I was desperately scanning the shelves, I don't normally open things before I've paid for them but I totally would have popped a few right then and there had they had some. Luckily the nausea passed.
Hope yours was a one time thing!