My dad had shingles and it was (and continues)to be very painful. His started out with tiny red bump on back of head. Doctor thought it was bug bite he itched. Too late found out it was shingles. There is a med you can take but in very early stages of shingles.
So tomorrow morning please get yourself into your doctors for a correct diagnosis. Please! (I realize you went to er, but doctors can make mistakes-re: my dad's doc not recognizing his case of shingles early enough for med to help)
Whatever it is, you need a doctor that recognizes the symptoms and gets you on correct path to healing.
Kat