Underestimate

I feeling comfortably numb, please don't mistake that for me being dumb.
Trust I'll never be under the thumb.
I am a free spirit, I love to be random.
I'm not your average girl of the stuck up British.
Maybe someday, I'll take up a fetish.
I say what I think, I might send you to the brink.
Just one piece of advice, never underestimate me I have hidden layers you might never see.