Hi DAP and welcome to the forum. I agree with what Tom said especially with keeping track of what you are eating and drinking to see if there is something specific that may be causing your nausea. The only other things I can think to ask is if you are sipping your liquids slowly, chewing your food very, very well and not eating or drinking too much at a time. Your tiny new stomach does not hold much and it takes getting used to stop eating and drinking before it gets too full. Another thing that will cause nausea is not getting enough fluids. Nausea is the primary symptom of dehydration. Maybe try increasing your fluid intake but remember to sip slowly and stop before your pouch gets over full. Another thing could be lactose intolerance. This is easily treated using OTC lactose enzymes that you chew or swallow depending on the brand. Constipation will also cause nausea. A fiber additive or stool softener will take care of that problem but you need to use something that is approved by your surgeon.
If these things do not work in reducing or eliminating your nausea you should call your surgeon's office so they can help you figure out what is causing this issue.