Thanks for writing to health care magic.
Pain in chest below the sternum
could be because of several causes. The symptoms you are giving are suggestive of reflux disorder. Here the acid in the stomach gets into the esophagus
damaging the mucosa there and resulting in symptoms that you are giving.
Try reducing your weight if you are over weight.
Do not lie down after a meal
try to reduce stress
If the symptoms persist your doctor will prescribe antacids and prokinetics to reduce the problem.
Hope this helps