The distended abdomen after meals could be because of:
- eating too fast (too much gas enters GI tract) : eat slowly, often and little
- high fiber foods : take malabsorption
- candida infection of GI : do culture of stool for candida
- do not lay down immediately after eating
You can schedule an appointment with a Gastroenterologist to further investigate and get proper treatment. Meanwhile, I suggest to eat less fiber and drink more water.
All the best!