Hi,
Welcome to the ehealthforum and I am really glad to help you out. Your concern is regarding the pain in the central and upper abdomen. All these symptoms are of gastritis due to acid reflux from the stomach.
It is usually after eating a heavy fatty meal and sedentary lifestyle. It can also be caused by drinking too much alcohol, prolonged use of nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin or ibuprofen, or infection with bacteria such as Helicobacter pylori (H. pylori).
Eat small nutritious meals at frequent intervals instead of a heavy single meal. Exercise frequently and take your dinner atleast 2 hrs prior to bedtime. Also raise the head end of the bed by 2 blocks.
Take some OTC antacid or Ranitidine. Also keep your fluid electrolyte balance optimum by drinking lots of fluids.
If the symptoms worsen then it may be due to H.Pylori infection.You need antibiotics in that case after prescription from a physician.
I sincerely hope that helps. Take care.