Stomachache after masturbation

Hmmm, well when you have an orgasm, your uterus physically contracts, so maybe that has something to do with getting a stomach ache. Maybe the contractions are too intense. Or maybe you’re subconsciously tightening your stomach muscles when you mas*erbate that when you finally do orgasm and release your muscles, you’re getting some kind of spams in your stomach, causing it to hurt. Try relaxing next time and see if that helps any. If it doesn’t, I would maybe go to the gyno and make sure everything checks out okay.