Hi there. At the outset to help you we may be in need of slightly more information vis-a-vis the gender you belong to & the technique used to masturbation please. This will enable us to pinpoint the reason for your abdominal pain. Masturbation per se should not be responsible for stomach pain nor should the frequency be an issue..again, which part of your stomach pains..is it the lower part just above the pubic area or higher? It is very likely to be either some sort of transient friction related transient UTI or a torsion of the cord/testes with referred pain depending on which sex you owe your alliegence to! (unless transgender lineage & then this opinion will vary).Please do use our premium ask-a-doctor package should you require further discretion! Instead of cranberry capsules, do go in for the more natural cranberry juice each morning which has more value added health benefits..& do get back to us with specifics please! Cheers & wish you a healthy sexual appetite & well-being! Dr Praveen Rodrigues MD Dermatologist, Cosmetologist, Venereologist Vikram Hospital, Bangalore, India.