I'm Just Recovering From Norovirus, Vomiting (briefly) And Then Dreadful

I'm just recovering from norovirus, vomiting (briefly) and then dreadful diarrhea from 4am Monday morning until this morning. After my last bout of diarrhea this morning I developed a rash all over my back and from my chest down to an inch above my belly button. It's not itchy and it's kind of merging together to create big red patches. My skin feels sensitive where my clothes touch it. I presume it's just a viral rash but obviously I'm worried that it's something else.