feeling nauseous 3 months after lumpectomy is this normal

Hello Sam, maybe you have a bit of acid reflux. Sometimes the drugs used in operations can upset your intestinal balance, and you can feel nauseous . I have had reflux for years it comes and goes. It sometimes is nausea. I also take digestive enzymes.
try a course of pro biotics, and see if a quick eze  helps. If it continues ask your Chemist for some over the counter tummy meds and see if that helps x I'm sure you'll be ok.
Peta