How does Carol Ann Duffy use imagery in Originally?

Imagery:

We came from our own country in a red room
which fell through the fields, our mother singing
our father’s name to the turn of the wheels.

All childhood is an emigration. Some are slow,
leaving you standing, resigned, up an avenue
where no one you know stays. Others are sudden.
Your accent wrong. Corners, which seem familiar,
leading to unimagined pebble-dashed estates, big boys
eating worms and shouting words you don’t understand.
My parents’ anxiety stirred like a loose tooth
in my head. I want our own country, I said.