I read something about a girl who was curious about sticking her finger into her cervix because she likes pain and she wanted to try it. I have heard about sticking fingers into the cervix and stuff like that too in BDSM circles and stuff. I'm kind of like the same way, I need sexual pain to get off. It's something that happened a while ago, although I'm underage you might say. So I have also been curious about it. I have read many stories of girls putting things inside themselves and through their cervices to reach deeper for that kind of sexual pain. Because I'm not concerned about having babies at all, and if I'm careful, I can still do that, right. I know you aren't for it but I was still just wondering how far I can actually go?

Inserting objects through your cervix is downright dangerous. You could puncture your womb and die of massive bleeding. Or you could introduce bacteria into your body and die of sepsis and/or toxic shock. If you are young, your cervical cells are immature and more prone to injury, defect and infections. Stabbing at them will not be healthy for your cervix. You're right, it can make you infertile. But like I said, it could KILL you. It's just dangerous. There is no safe way for you to do this.

What's more troublesome is that you have some psychological issues that should be addressed. You stated that something happened to you when you were younger, and it led you to crave pain as a part of your sexuality. While a lot of people enjoy BDSM safely and consensually in the contexts of healthy relationships, your hints of past abuse may be keeping you from developing healthy relationships now. I think you should consider getting counseling to address the incident from your past.

In case I have read you wrong and there are perfectly healthy reasons for you to want to incorporate masochism into your masturbation, I'd still suggest you not insert things through your cervix (the cervical os is only about 0.5mm wide, about the narrowness of a stick of mechanical pencil lead). Instead you may want to find safer ways to inflict pain, like pinching yourself (but not breaking the skin).