I Had Been Taking Azithromycin For Eleven Days For A

I had been taking azithromycin for eleven days for a bad sinus problem....three days after I stopped taking it, I had a dental procedure which I have to take amoxicillin for - 2000 gr. one hour before the procedure. I took the four capsules, and after the procedure, while driving home, I experienced itching in my ear, then my whole scalp, took me maybe 15 minutes to get home and by then my face was flushed and my palms itched and got red. Thankfully I had some benadryl in the house and after talking with the dentist she advised me to take the benadryl, which I did, but then never to take the amoxicillin again....suggested I take a different antibiotic...clindamycin. Any advice? Do I have to never take penicillin again? I realize now I should have postponed the appt. but I didn't...wait till the azithromycin was out of my bloodstream I guess. Thank you.