Return of morning sickness?

I am just past 35 weeks now, and the last two days have been plagued by awful nausea, reminescent of the first trimester. I have had a funky sinus/cold thing over the past week, but didn't have any stomach issues with it. Anyway, I'm wondering if anyone else has had issues with nausea or vomiting here recently? It has been so bad that I've resorted to taking Zofran again, just so I can get through the day without throwing up everywhere. I don't remember dealing with this during the later parts of my other pregnancies, but maybe I just forgot? And this isn't one of those things that happens when you're about to go into labor, is it? I'm not quite ready for that!