lactose intolerance usually passes when the food is digested, so 3-4 hours. initial symptoms are bloating, gas, cramping and often d. I have been LI for about 15 years. my guess is you set something off like a little attack so your tummy is just "off" I'd avoid dairy and greasy stuff today and focus on carbs and protein to sop it up. also try to drink lots if water to flush your intestines.