I often feel like my food is not being digested hours after eating, but my stomach is growling. why is that?

+/- Gastroparesis?: Consider gastroparesis=a slow-emptying stomach that is most symptomatic after the stomach fills from meals. Maybe its functional due to brainstem reflexes induced by eating--often exaggerated in irritable bowel syndrome resulting in altered perception of gut distension, "growling", &modified transit of food. Sometimes, gastric outlet delay may reflect inflammation, scarring, biliary disease, more.