I'm no expert, but what I'm seeing is that you are trapped inside structure.
I'm guessing that this structure is some kind of mind set/attitude/belief
as you cannot escape it.
Where ever you go, .... there you are.
You can not escape yourself.
There's really a lot going on in this dream and I find myself getting
scattered trying to figure out what aspect to approach first.
So rather than do that I will ask you some questions:
How do you view birds in general?
Like them, dislike them, envy them....why?
How do you feel about your body?
Like or dislike, indifferent and why.
Do you feel comfortable in/with your body?
Yes, no, sometimes, when, and why.
How do you feel in this dream?
What adjectives would you use, like determined, or frantic.
What colors dominate in the dream?
Colors often set the mood/feeling.
After you determine how you feel in this dream
look at your life and try to identify any circumstance/situation
that produces the same feeling in you.
When you can connect the feeling to real life you will have a better understanding
of just what this dream is all about.
Wishing you the best,