What could cause painful bumps on tongue after eating?

Allergy: Might be food allergy or possibly "oral allergy syndrome" which is related to pollen allergies but caused by some raw fruit and vegetables.

Glossodynia: Your tongue is covered by taste buds but they don't all look the same. On the front of the tongue are two different types of taste buds; the longer ones rise above the surface of the predominant shorter ones. At the back of the tongue are a chevron of round taste buds that people often mistake for pimples or abscesses. Tongue pain is hard to localize. If it the pain persists see your physician.