I Am On Day 3 Of Azithromycin For A Bad

I am on day 3 of azithromycin for a bad cold / sinus infection (sick for 6 days now). I have also been taking mucinex every 4 hours for the last 3 days. I just noticed that I have a rash all over my torso, but was hot and sweating just before that. I am 49 years old and told since I was a little child that I am allergic to penicillin, which I informed the doctor of. and I am still feeling heat on my body. My breathing feels normal to me - just feeling hot all over that's all and the rash. My heart feels normal and breathing is fine. Do I need to do anything?