or Shingles?

So, I have been with my boyfriend for 4 years in a completely monogomous relationship (Yes I'm SURE) This past week I contracted a type of rash in my genital area. I went to the doctor and he took a blood test but he said he thinks it is ! I don't see how that could be since neither me or my boyfriend has ever had it. I mean his mom is prone to getting cold sores on her mouth when she is stressed, but he has only ever had a couple cold sores in his life! I'm really upset and stressed out waiting for my results... any answers?