Hello, I read carefully your query and understand your concern. The cramps are normal after masturbation. When a woman orgasms, there are contractions of the muscles of the uterus.  If the cramps are to painful you can use painkillers and warm compresses at the abdominal area. Hope my answer was helpful. If you have further queries feel free to contact me again. Kind regards! Dr.Dorina Gurabardhi General &Family Physician