A child is a symbol of innocence.
There are two interpretations for a child.
#1) If you were the child, you need to get in touch with your own
innocence. If you, as the child, were in trouble, you need to go
beyond your innocence and acknowledge the ways of the world.
Everything is not all sweetness and light!
#2) If you were watching children playing, this is a sign of
success and happiness, both in your personal and professional
life.
But since you are experiencing the child pressing against your
chest, giving you pressure, it could mean that you are trying to
deal with some issues in your life which is currently a burden to
you. Too much of such pressure is affecting your sleep at night,
thus your unconscious is letting you know that you should deal with
it at one.