Dear user, Thank you for writing to Healthcaremagic. I can understand your concern. Sexual activity (intercourse or masturbation) in certain positions may cause back pain, neck pain or pelvic discomfort. It may last for hours to days. This occurs due to musculoskeletal reasons. You can try different positions other than that causing pain. If pain persists, consult orthopedics surgeon. Oral pain killers with muscle relaxants and topical applicant creams help for this. Man do have refractory period soon after climax (varies from few minutes to hour) during which you cannot have erection again. This is normal thing. Lack of interest in sex with spouse and more in masturbation suggests that masturbation gives you more pleasure than sex with partner. I suggest to consult sex therapist for discussing and exploring causes of insufficient pleasure with partner. Wish you good health.