Given the symptoms you reported (nausea, heartburn, high acidity level detected, frequent burping), it is possible that you might be experiencing gastroesophageal reflux disorder. Gastroesophageal reflux disorder is a condition in which the gastric acid from the stomach enters the esophagus. If the condition becomes chronic, the acid might cause irritation and inflammation of the esophageal mucosa. This inflammation is presented with pain behind the chest bone, usually described as heartburn. The pain might also be detected in the back between the shoulders.


The causes for this condition might include a weak sphincter (closing muscle) at the entrance of the stomach, incompetence of the lower esophageal sphincter or hiatal hernia. Aerophagia (a condition in which air is swallowed), might have caused the constant burping which is accompanied with the acid reflux.


The hiatal hernia would have been visualized on the X-ray. That might leave the aerophagia and the high acidic level as possible causes, because the weak lower esophageal muscle usually is not a temporary condition.


A gastroscopy done by a specialist for the upper gastrointestinal tract (whom you are advised to visit) might be helpful. If reflux is detected, antacids might solve a great deal of the problem. Changing eating habits (eating slowly, not eating large quantities of food that might overextend the stomach) might additionally reduce the symptoms.