I'm not sure how to criticize music, so I'll just have to say what I feel about it.
The intro definitely sounds like a lullaby, and calms me just a bit. Nice use of chimes, or whatever sound you used in the creation of this lullaby. I think it's from 00:00 to 00:20, after that the notes start to 'overlap' and goes off-beat. This stops at around 00:53, and becomes relaxing again.
The middle, particularly the part with high sound (waves?) took me by surprise. It honestly doesn't fit a lullaby, and woke me up a little bit inside (no pun intended). Once 1:50 started, I heard someone mashing the piano. It doesn't provide a good transition to the soft, and peaceful lullaby feeling.
The end is quite nice, but is a little too quiet even for a lullalby. I supposed it's a good change of pace.
Maybe this music video could help out in your future music making: