What is this stomach rumbling I feel? I ate hours ago.

Food allergy? Food allergies often present with bloating and gas or loose stools yet some have constipation, skin rashes, joint pain, etc. As a result so can vary. Testing for food allergens is different as it requires digestion and absorption till side effects are noted. Look for a functional medicine doc that can help you with IgG food allergen testing thru metametrix or similar lab to diagnose it properly.