2. Nausea
Once again, feeling nauseous is normal from time to time. After you eat something bad or if something simply disagrees with your digestive system, you may get this feeling. However, feeling nauseous all the time or fairly frequently is not normal.
When cancer cells are growing in your stomach lining it can cause you to feel quite ill most of the time. While you may not be vomiting or have any other type of symptom, feeling frequently nauseous is not normal and should be discussed with your doctor.