Periodic pain every minute to minute 1/2 in stomach area about 5 inches above the naval. ate some late night snacks including ate some late night snacks including bread and milk just a while after having a beer.

Impossible to say: What is causing it just from that description. A beer is unlikely to cause gastritis, and most pain from either gastritis or ulcers gets better with food. There are hundreds of possible explanations, including pancreatitis, but nobody can make a diagnosis without a full history, examination and probably laboratory tests. See your doctor.