The stomach and the intestines are involved in the process of food digestion. The presence of food triggers a series of actions, including: producing different gland products (stomach acid, bile, pancreas and intestine secretions) and peristaltic contractions of the stomach and the intestines.


If you have not taken enough food for a longer period then you might experience sudden production of stomach acid which might feel like mild stabbing pain in the upper abdomen. The contractions of the stomach are probably responsible for the burping, where the contractions of the intestines are probably responsible for the wind. Both the burping and the wind might have a bad smell (rotten egg as you described) which is a gas product of the metabolism of bacteria that are normally found in the intestines.


To summarize, the symptoms you experienced (cramps in stomach, burping and wind when taking food after not eating for two weeks) are considered completely normal and it might take a few days of normal and regular meals in order to restore the previous condition of your digestive system. If you experience the symptoms further you might want to visit a specialist for gastrointestinal disorders for an additional physical examination, laboratory tests and/or gastroduodenoscopy (endoscopy of the upper gastrointestinal tract) if needed.