Blood in the urine returns to normal the next day, but back pain may be the effect of urinary stones, pyelonephritis, tumors and other diseases. 1. Urinary stones: blood in the urine returned to normal the next day, but the back pain may be suffering from urinary stones, such as kidney stones, ureteral stones will bring blood in the urine, back pain symptoms, accompanied by urinary urgency, urinary frequency and other discomforts. 2. Pyelonephritis: blood in urine returns to normal the next day, but back pain may be suffering from pyelonephritis, acute pyelonephritis attack will be blood in urine, back pain and other symptoms. 3. Tumor: blood in urine returns to normal the next day, but back pain may also be a tumor, kidney tumor or ureteral tumor, tumor ulceration and bleeding and blood in urine, bleeding caused by blood clots blocking the ureter or renal pelvis after the symptoms of back pain. The blood in the urine returns to normal the next day, but the symptoms of back pain, you should go to the regular hospital as soon as possible to find out the cause, so as not to delay the condition.