No, She isn't a dragon. She can't breathe fire, or any element. This is a Supernatural green b/ood's real form. The human body form is just a disquise to throw off the enemy's perspective.
What the supernaturals call this form is "Trantcye Shade". In other words, this form is called "The Sly Shadardow"

Never underestimate A Green B/ooded Natural. The structure of The Sly Shadarow is made for sneaking up, Attacking unexpectedly and to destroy it's target.
Can also shrink and grow.