Cluster of blisters

I've been staying in the hospital for quite a while now due to high blood pressure. Last night my shoulder blade area was really itchy but I couldn't feel anything when I scratched. This morning I woke and it was really itch again so I scratched and it felt wet so I went and looked in the mirror and saw a cluster of blisters. I called the nurse and she said it looked like ringworm and wasn't too concerned. Another said it looks like a dry patch and gave me some cream. It's been a few hours now and it kind of burns. I'm trying not to freak out but I don't know what this could be or how I caught it. I have hsv 2 but have been on acyclovir for a week now for babies protection and plus how could I possibly get it on my back??? Also, I've never had chicken pox so it can't be shingles. Has anyone had this?