My stomach hurts even after eating a small portion of food. It's dull pain in the upper ab. It also seems to take a long time for me to digest food.?

Possibly Gallbladder. If the meals contain fat, it could be related to gallbladder problems. You could also have some kind of a stricture in the esophagus. In either case, you should have an evaluation by your primary care doc. S/he may even send you to a gastroenterologist.
See a doc. There are many possibilities for the problem you describe, too complex to discuss in this forum. You need to consult a physician.