I may be chiming in late on this, but to echo what others have said, go to ER. If you need a ride, call the paramedics. They will hook you up with fluids if you are dehydrated, and as an extra benefit, you will get into a bed faster than jonesing in the waiting room.
Your life is at stake when you are detoxing. The bills can be paid later.
Oh, just another thought; in some states if you apply for the state healthcare and qualify, they will cover some back medical payments. Ask your social worker while you are at the hospital. Good luck. Most of us have been there and gotten the Tshirt.