Nausea is a symptom of stomach acid because the acid from your stomach comes back up through your esophagus. This causes irritation to your esophagus and also leaves a bad taste in your mouth so you feel nauseous because of the back up of acid in your stomach. Some of your symptoms if you also have stomach pain and loose stools or constipation may be a sign of Irritable Bowel Disease also known as spastic colon. This can also make you feel nauseous right before and after you eat.
