Melissa, I've had all the thoughts and no longer have them. It's garden variety anxiety/panic/obsessive but your mind wants to tell you your unique, it's something chemical, your bi-polar, schizo, you name it. Reality is that if you were, you wouldn't be posting your thoughts here and you wouldn't think their insane (which would really be insane!)
I've had all the same thoughts, as have others. we all knew they were insane, we all felt sick and ashamed for thinking them and yet they'd keep coming.
A thougts a thought and it has a lot of power when it's a secret and your fearful of it. Get it on the table, acknowledge it's insane and don't recoil from it or avoid it and it loses all it's power. Recoil, grab on, run and it just escalates.
The same is true of any thought whether it's diving through a window, hitting another car head on, drowning while giving bath, dismembering your child while cutting something with knife, whatever the "insanity of the day" may be.
To someone unfamiliar with anxiety/panic you mention this to them and their ready to have you committed. Mention it to someone that's lived it, they understand, don't judge, know your not going to act and it loses all power.
You see or hear something on the news and all the sudden your obsessing that it could be you if you "let go". The reality is that the more you avoid and recoil the more power it has and you become consumed.
Tons of people have gone through it and it's garden variety panic/anxiety. Don't be ashamed, don't run from it, do as your doing here by sharing and it will lose it's power. (while your mind is saying, you better not let go or your gonna snap!
Don't recoil and move on. Trust me, if you were insane, you wouldn't be acknowledging how crazy the thoughts are. If you don't fear them, just acknowledge their crazy and move on, they lose power and will disappear.
Now go hug your kid!