Week 5. - What is my baby development at 5 week ?

I can briefly lift my little head when lying on my tummy. However, it is difficult for me due to the fact that my neck and back muscles are not developed yet.
You can notice my smile, but, for now, it will be an unconscious smile, called the reflex smile.
I can locate the source of the sound and I can move my head towards it.
I know how to differentiate between your voice and other voices or sounds. It is your voice that calms me down and makes me feel safe.
If you tickle my soles, you will notice that my toes curl downwards, except the big toe, which curls upwards.