So, when a patient presents with a gastric upset, or indigestion, there can be several things going on. But the most common situation is called gastritis. Gastric refers to stomach. Itis refers to inflammation just as you can have, tonsillitis, inflammation of your tonsils. Gastritis is inflammation of the stomach lining. Gastritis is usually a self limiting condition, but when it becomes problematic and problematic situations are when it alters your daily activity may affect your asleep, your wellbeing. And especially if this has gone on for several days or definitely within two weeks period of time, you should definitely bring it to the attention of your health care practitioner.