Gastroesophageal reflux disease (GERD)
Gastroesophageal reflux disease (GERD), or just acid reflux, is when stomach acid frequently flows back into the esophagus. Heartburn is the most common symptom of GERD.
Dyspepsia
Dyspepsia, or indigestion, may cause upper abdominal pain, burning or heat, and the stomach feeling full during or after eating.