Hello there....., Most kidney stones are small and pass out with the urine. Some stones become stuck in a kidney or in the tube draining urine from the kidney (the ureter). .... Most kidney stones will be small enough no more than 4mm..to be passed out in your urine. It may be possible to treat these at home. However, small kidney stones may still cause pain. The pain from smaller kidney stones usually lasts a couple of days and disappears when the stone has been passed..consult Urologist....