No, hitting your head with your pillow while you're sleeping has absolutely nothing at all to do with autism and there's no reason to think that it does. If you're hitting your head with your pillow in your sleep this is fairly normal.
babies get to sleep just the way we do
Because it's more comfortable than sleeping with their head in the air. 
The baby usually hits themselves in their sleep as they are being troubled by flies and other insects spoiling their sleep.
never ever let a child lay down after they hit their head, keep the child upright and awake then see a physician.
The Sleep of Babies was created on 2008-11-19.
yes, babies sleep in the womb but that does not mean they are always sleeping
of course you can sleep after you hit your head. its no big deal. However, you may get unconscious or if the hit is really hard, you may have a concusion which may lead you to have a bad headache while sleeping. Seeking professional help should be done if these sypmtoms persist
No
Babies sleep when they are tired. They usually are awake for two to four hours at a time when they are new borns.
Either face of the head is the hitting surface.
My hamster is nocturnal but I think babies sleep more than adults:)