Hi, Thanks for posting in HCM. I understand your concern. Masturbation is the sexual stimulation of one s own genitals for sexual arousal or other sexual pleasure, usually to the point of orgasm. It is a natural phenomenon. It releases your sexual pressure by yourself. Thus it eases your sexual tension and so it improves your health. Your body produces semen that can not be stored unlimited and hence nature tries to ejaculate it by night fall or induces the person to masturbate. You don t have to worry as it will not cause any harm to the body. Masturbation does not lead to kidney pain or kidney failure. You might be experiencing pain due to physical exhaustion. Kindly take analgesic medication to overcome it. Kindly get yourself evaluated by undergoing ultrasound scan of the abdomen to know weather there could be kidney stones, which could be causing pain. You can consult Urologist with report for appropriate evaluation and management. Hope the information provided would be helpful. All the best.