Upper endoscopy shows nothing wrong - definitely not gerd. What to do next for stomach burning?

Stomach burning. An endoscopy cannot necessarily rule out Gerd, because it is possible to have Gerd without any visible findings on endoscopy. Often after a negative endoscopy a trial of medications is given to see how your body responds. Otherwise, further testing may be necessary. Good luck.
For pyrosis symptoms. Can have symptoms w/o damage. Avoid foods & behavior that delay stomach emptying &/or relax the lower esophageal sphincter--spicy, greasy food, mints, alcohol, tobacco, chocolate, tomato-based products, caffeinated & fizzy drinks, eating before bedtime. Lose weight. Elevate head of bed on blocks. Use otc acid blockers for relief (h2's: tagamet, zantac, (ranitidine) pepcid; ppi's: prilosec, prevacid, zegerid).