What Causes Itchy Rash On Corner Of Mouth With History Of Shingles?

I have a circular rash on the right corner of my mouth . I had a bunch of them on the back of my neck that come and go I had shingles 3 years ago and got a shingles shot to prevent getting it again it was so painful could this be reacurring again but not going to the blister stage just a itchy an spreading rash