In her mind the idea of having the baby scared her so much she went overboard. Her reasoning that way was most likely "oh god oh god oh god I can't have this baby! I can't! What do I do?!?!". It was incredibly stupid. Having sex so young, unprotected, hiding it, having it in a toilet, she's a massive idiot. Though I feel kind of sorry for her in a bizarre way. There is no way she will ever lose the mental scaring of killing a baby. Maybe if she had just changed one thing her life and her babies life would have been okay.
Is that how we now describe people who suffocate infant to death with bare hands?
I was thinking more in line of cold hearted murderer.