What could be the reason for nausia in the morning other than being pregnant? I am on birth control pills and just saw my obgyn and I am not pregnant.

Acid Reflux. Dont forget acid reflux if you have heartburn. Lying down brings gravity to bear on acid that already wants to move up the esophagus. Irritation of the lower esophagus can instigate nausea as well as the irritation of the stomach lining itself.
Nausea. Make sure you check your liver and gallbladder as well. Nausea can be a sign of liver disease.