What Causes Swelling And Rashes In The Inner Mouth And Cheeks?

Swollen inner mouth that started with a bloody rash under the surface of the skin. Rash has spread into my cheeks now. I have a raw, dry and metallic taste/feeling in my mouth. Been to doctor who suggested it was an allergy. 2 colleagues at work also experiencing similar symptoms. What do you think it is? I have allergic rhinitis and am on nasal steriod spray and anti-histamines 24 hours. I am 35, healthy female.