It is recommended to go to the hospital for examination to clarify the possible causes: 1. The presence of pyelonephritis, which can be accompanied by symptoms of urinary tract irritation, such as urinary frequency, urinary urgency and pain and burning in the urethra during urination. 2. The presence of urinary tract stones, such as ureteral stones or kidney stones. If you have a urinary tract stone, such as a ureteral stone or a kidney stone, you may experience back pain when you urinate, along with urinary tract irritation or hematuria, and it is recommended that an ultrasound examination of the urinary system be performed to rule out the presence of stones. 3. However, if there is a relevant lesion, such as a lesion at the ureteral opening or a tuberculosis in the urinary system, it will cause urine to reflux through the ureter into the renal pelvis, and then some of the urine will be expelled from the body during urination, while some of the urine will reflux into the kidneys and symptoms of back pain will occur. This is usually accompanied by symptoms of urinary tract irritation and, in the case of tuberculosis, fever or night sweats, which require relevant tests and, if necessary, even imaging to determine the presence of vesicoureteral reflux.