Does Pain And Rash From Breast To Back Indicate Shingles?

I am in quite a lot of pain and I have a rash that is from the front of my right breast spreading round onto my back. I have some steroid cream but it doesn't seem to be doing any good and I have taken some ibuprofen but even that is no longer doing any good. Is it Shingles ? I have not had pain like this before. Thank you