I am 8 weeks post op and to this point its been a breeze including great weight loss. All of a sudden have developed a mild constant nausea. Nothing specific about diet change that I can figure but have cut back on protein shakes. I have probably not kept up my water intake would this be a possible cause? Has anybody experienced a similar situation?

Could be a mix of the Protein (maybe you're developing a reaction) and also keep up with the Water. The water does so much to help with more than just hydration.

Look at the type of protein, I've seen people over time say they developed a reaction to whey, soy, and even egg. So far I haven't seen any probs with the veggie ones.