Is shingles meant to be this painful?

F31 Went into my out of hours with extreme pain in my right shoulder that radiates around to my chest. It’s a deep pain and there’s no surface pain at all, or rash. I was given antivirals and told it was shingles, but I’ve never had this before… I couldn’t move from the pain last night again and only over the counter codine would touch the pain enough for me to think. The pain itself lasts about 2 hours before gradually tapering off… it was about 6 hours the first time but I’d only taken codine after ibuprofen and paracetamol failed to calm it.

It’s been 4 days since I was told it was shingles but still no rash, just periods of extremely intense pain with little other symptoms. The pain is only on one side and despite radiating to my chest it seems to start and be most intense under my shoulder-blade I’m on antivirals for the next seven days but should it hurt this much without a rash? Not sure if I should stick it out or go back to my GP (Uk)