You may feel a pain in the stomach after eating for the following reasons:
You may have a food allergy to some types of food, such as milk, soybeans, nuts and eggs
The digestive system is unable to tolerate and digest some foods, thus causing stomach irritation and digestive disorders
Many foods that irritate the colon include insoluble fiber, fried foods, legumes, and caffeine.
You may have a stomach ulcer
You may have irritable bowel syndrome
Artificial sweeteners are one of the causes of stomach pain after eating.
I advise you to review your doctor to find out the real cause