Develop allergies/hives during pregnancy?

Jojaira

I have no known allergies. Have never experienced anything like this. Today I had a burger the only ingredient I normally dont eat is jalapenos. Took one bite n took out the rest. Had an ice cream a few mins after. And started to feel itching in my tigh area. When I got home this is what I found...any ideas? Should I be concerned? Have a few other randoms throughout my body but this was the most "severe" area.