Hey all. Thanks so much for your help. I went on a grocery run last night and came home with bananas and rice cakes. But the best thing was something I already knew about but had forgotten.
A company called Glutenos makes a gluten free (and therefore wheat free) pretzel. They are delicious. I'm going to post a link here in case anyone else is looking for wheat-free or gluten-free things to nibble on when nauseated. http://www.glutino.com/our-products/snacks/pretzels/pretzels-sticks-8oz-us/
I haven't tried them yet for nausea nibbles (so far my queasiness tends to hit mid-morning) but I think they are going to be the perfect saltine substitute.