Every time something major happens in your life, there's a good chance that you'll step back and take a few moments to contemplate how it's changed the way you think or behave in the world. And let's face it: becoming a mother is a pretty massive change. Our speaker sure thinks so, at any rate. "Morning Song" may seem to be about how a new baby acts in the world, but it's also an opportunity for a new mother to play out her changed sense of self.
The speaker doesn't know how to view herself since becoming a mother. She's unsure if she should think of herself as a distant creator, a food source, or a caretaker.