I Had A Shingles Shot Several Years Ago But I

I had a shingles shot several years ago but I haven't gotten the 2nd shot that is now recommended. Lately, I have had an occasional papule in the neck and upper chest area. It is not a pimple but more like a small fluid filled thing. It pops, then eventually heals. Could these be shingles that are mainly suppressed because of the immunization I did have? Occasionally they feel like they are burning.