Pain in the small abdomen after urination is recommended to go to the hospital for further examination to clarify the possible causes. The possible causes are: 1. Acute cystitis. When cystitis occurs, pain in the small abdomen after urination can occur. In severe cases, there may also be symptoms of urethral bleeding after urination, mostly accompanied by symptoms of urinary frequency and urgency. It is recommended that routine urine and urine culture tests be performed to determine the presence of cystitis.2. Bladder stones or stones at the end of the ureter. They can be associated with pain in the small abdomen or pain in the small abdomen after urination, and are accompanied by symptoms of back pain, abdominal pain, urinary frequency, urinary urgency, etc. They can also be accompanied by symptoms of hematuria in the naked eye. Ultrasound examination of the urinary system is recommended to rule out the presence of urinary stones. Polyps or tumors in the bladder can also cause pain in the small abdomen after urination. The pain is not obvious in the early stage, but when the tumor increases in size, it can cause local pressure and produce local pain symptoms.