Mine always came in waves as well.
It kind of felt like a cross between a hangover (because I felt so tired as well as sick), and having eaten something funny.
I also had a very, very sensitive gag reflex with both of my pregnancies from about six weeks. Just getting up off my chair would cause me to gag, it wasn't just smelling food or whatever. Worse when hungry for me too, I pretty much snacked all day long to keep it under control.
Geez just thinking about this is making me feel queasy LOL.