Suddenly feeling short of breath in the morning, stomach pain and pain in the whole abdomen may be a sign of perforated gastric ulcer complicating acute peritonitis or myocardial infarction. Sudden shortness of breath, stomach pain, and generalized abdominal pain in the morning after waking up may be a sign of acute peritonitis complicated by a perforated gastric ulcer. The patient may initially have only stomach pain and sympathetic excitation, causing shortness of breath. When the stomach is perforated, the gastric contents enter the abdominal cavity, which may cause full abdominal pain, muscle tension, and a slab-like abdomen. A sudden feeling of shortness of breath in the morning, stomach pain and pain in the whole abdomen may also be a sign of myocardial infarction. In addition to stomach pain and full abdominal pain, patients may also feel pain in the shoulders, neck, and even upper extremities, often due to nerve involvement. The sudden feeling of shortness of breath in the morning, stomach pain, and pain in the whole abdomen may also be caused by other reasons, and it is recommended to consult a doctor in time for targeted treatment under the doctor’s guidance. Please do not take medication on your own to avoid delaying your condition.