New food allergies??

Had anyone developed food allergies during pregnancy? I’m 28 weeks pregnant. I’ve never had any type of food allergies before but today I went to a restaurant and ordered a Caesar salad. I ate about 3 bites then just didn’t feel right so I didn’t eat anymore. On my way home it started to get difficult to breathe. Once I got home my eyes were itchy, red and swollen, my throat was swollen, my lungs were tight, my nose was completely plugged, my stomach hurt and I was bloated. I thought I was going to have to go to the hospital because it was so difficult to breathe but once the Benadryl kicked in I felt fine again. My friend who is an OB nurse thinks I might be developing an allergy to the anchovy’s they use in the dressing. Has anyone ever had this happen??