Could be acid reflux. Belching is a symptom that you may have even if you don't have any heartburn. That is how my reflux started.
There are some OTC reflux meds you can try...Zantac, Gaviscon, Prilosec, Prevacid (new on market this month).
Watch your diet. Avoid carbonation, caffiene, spicy foods, high fat or greasy foods, tomato and citrus products, alcohol, tobacco, etc...
Try to wait at least 3 hours after eating before lying down.
Limit your bending after eating. It squeezes the stomach and pushes things up.
Wear loose fitting waistbands on your pants and don't tighten your belt too much.