Do you really HAVE to go to work? Shingles can be stress triggered and work usually makes that worse, and I think it will make you tired etc. on top of the fatigue I imagine you get anyway. From what I understand, you might get some symptoms if you are running a temperature, but that this isn’t a relapse and will pass once the temperature passes.
Another point about work is you will be contagious to anyone who has not had chicken pox, and anyone in early pregnancy can have quite serious complications if they get chicken pox, so I’m surprised work actually want you in.
Hope you get better soon.