I believe this is called "denial". If you're open to having a baby, and not using protection, and having sex.....well, being in denial about how babies are made doesn't really change the fact that you were doing exactly what people do when they try to have a baby. It might do you well to accept your reality. Denial is not a method of birth control. If you don't actively WANT to be a young, single mother, then you should start using birth control. It's really that simple.