Hello, and I hope I can help you today. I do not know how old you are, but if you are having vaginal bleeding and cramping and are of an age where you might menstruate, it is possible that you just got your first menstrual period. However, if anything was placed inside your vagina during masturbation, it is possible that you may have torn or cut yourself in a small way which also could have caused bleeding. The way you will tell the difference is by wearing a maxi pad and waiting and seeing about what happens with the bleeding, if the bleeding increases, especially looks purple or brown, it is most likely your first period. If the bleeding is bright red like you cut yourself, and stops rapidly (within 24 hours) it is most likely that you may have injured yourself during masturbation, but only if anything was placed inside the vagina. Masturbation itself is not physically harmful. Some women do get uterine cramps when they have an orgasm, but this is normal. The majority of girls and young women do experiment with masturbation, so your situation is not unique and is not anything you should be ashamed of. If for some reason you do find out that you may have scraped or cut yourself from masturbation, it will heal just like any other cut or scrape on the body. You are still a virgin until you fully rupture your hymen during sexual intercourse, and a small injury will not change that. So, the best advice I can give you is to wait and see what happens with the bleeding. Either way, the fact you are bleeding is not concerning and most likely is something completely normal. I hope I was able to adequately answer your question today, and that my advice was reassuring. Best wishes, Dr. Brown