Hi,
Welcome to health care magic,
Stomach bloating is caused mainly because of air swallowing known as erophagia.
The other causes are
irritable bowel syndrome,dyspepsia, constipation ,
celiac disease,sprue,bowel obstruction etc.
If you have
abdominal bloating or distension with vomiting,diarrhoea and constant pain then you should start some medication like proton pump inhibitors (
pantoprazole),antispasmodics,pain killers with avoid excess carbohydrates and fatty foods, avoid oily and spicy foods.
You can continue pepto bismol which you are taking but you may also need to take appropriate antibiotics.
You should do some routine blood works,ESR,electrolytes and if required then ultrasound abdomen.
With symptomatic treatment you will feel better within 2 to 3 days and If you still have these problems then you should go to gastroenterologist to treat underlying cause.
Regards,