Abdominal pain can be felt anywhere between thorax ( chest ) and pelvis.  Pain could be mild, moderate or severe. It may be dull or acute.

Almost everyone has experienced abdominal pain, one time or other.  Most of the time, stomach pain is not serious, but severe abdominal pain is a cause of concern.  If pain starts suddenly and unexpectedly, it should be regarded as an emergency, and investigated accordingly.

References: www.nhs.uk 
www.nlm.nih.gov 
www.nlm.nih.gov 
www.ncbi.nlm.nih.gov

Pain in abdomen can be of various intensities and nature. It can be:

·         Sharp, stabbing cramp like pain

·         Brief pain that may come or go

·         Pain associated with vomiting

Reference: www.nhs.uk

·         Abdominal infection

·         Appendicitis

·         A perforated peptic ulcer

·         Gallstones

·         Kidney stones

·         Diverticulitis : Inflammation of small pouches that are part of the bowel

Other common causes in adults are:

·         Irritable bowel syndrome

·         Crohn's disease

·         Urinary tract infection

·         Long term Peptic ulcer

·         Constipation

·         Heartburn and acid reflux

Common Causes in children

·         Constipation

·         Urinary tract Infection

·         Anxiety

·         Heartburn and acid reflux

References: 
www.nlm.nih.gov 
www.nhs.uk