You're not a piece of shit. Don't ever think that. You're just overwhelmed atm and teenage DC do know how to push us to our limits.
I'm saying this as a mum who had to involve social services and the police when my DC were teens because I was desperate for help.
If you can, take a deep breath and try and find some calm in yourself. Then, go somewhere private with your DD or take her to a cafe, somewhere neutral, apologise and be honest. Say you're finding her behaviour challenging, ask how you can work together to make both of your lives easier. I know that sounds a bit like giving her control, and it's bloody hard, but if you can start communicating, it will make things easier.
Also, things like her room being a tip, shut the door and don't go in there. I had to do this and, without fail, every two weeks my pain in the ass teen would disappear with bin bags, dusters and polish and reappear to put the washing machine on, wash plates and take out rubbish.
Just try and remember that you are the adult. You've totally got this.