Kidney stones in both kidneys, if not causing obstruction, usually do not produce obvious clinical symptoms, or only show soreness and mild discomfort in the lower back. When obstruction is caused, renal colic, hematuria, and even difficulty in urination, vomiting and other symptoms can be seen. 1. No obvious symptoms: As the stone is not obstructed, the urine is discharged smoothly in the kidney, and the ureter is not jammed without spasmodic dilatation manifestation, so there will be no symptoms. 2. renal colic: when ureteral obstruction occurs, the fluid in the kidney increases, the intra-renal pressure increases, the stone and the ureter produce jamming, spasm, and renal colic occurs. 3. hematuria: when obstruction occurs, the stone and ureter jamming, resulting in ureteral mucosal damage, and hematuria. 4. Difficulty in urination: when stone obstruction occurs, urine cannot be discharged normally in the kidney, resulting in difficulty in urination. 5. Vomiting: due to renal colic, the visceral tugging reflex occurs, resulting in the symptom of vomiting. If you have any of the above conditions, it is recommended to go to the hospital as soon as possible to avoid delaying your condition.