Itchy rash hives burning

Patient: Hello I have a itchy burning rash. My mouth thingies. I went to er they said its shingles. My primary Dr said allergic reaction. The allergist gave me prednisone. Im am still itchy and breaking out more. My mouth still thingles. What do you think is wrong? I ask the allergist if he can do blood work or scrape my skin to test he said he doesn’t have time he sees patients every 10 minutes. Im going to get a 3rd opinion with another allergist. This is going on 3 weeks.Thank you [email protected]

Symptoms: Itchy, rash, hives, burning in body, itchy mouth. Thighs, legs knees and elbows covered.