If you don't have a primary care physician, perhaps you can go to a walk-in clinic and use them to guide you through the process. Try to avoid going from one doctor to another on your own. Have a primary care physician, or nurse practitioner that you can come back to to discuss the situation and decide what to do next.
I have a “Cadillac Plan” and a great Primary Doc. I went to the ER because I was in a lot of pain suddenly in the late evening, not because I am penniless with no insurance.