Analysis of Up in my room on my unmade bed

Up in my room on my unmade bed
I sat and read.
There was work waiting for me below.
I didn't go.
For in my little green room the song
Flickered along.
If the singer had seen the way it fared
She would have stared,
Have wondered and stared at me who read
With tumbled bed,
Wide-open window, wide-open door,
Books on the floor.
Hers was a disciplined, comely, wise
Christina-guise.
But what's the hell of a mess to me
When I am free
And wind blows in and a delicate song
Flickers along.