rash with fever

Hello, I thought I might have shingles because a new rash on my neck was accompanied by low grade fever, headache, diarrhea, fatigue and malaise. The symptoms appeared last week, were better for a few days, and came back again.

Skin biopsy showed "fine parakeratosis, spongiosis, and superficial perivascular lymphoeosinophilic infiltrate." I have written the doc.

Could be allergy (contact dermatitis), eczema, could maybe relate to an autoimmune condition (I have a systemic lupus diagnosis).

Has anyone had a rash with fever and other symptoms? Not COVID, not the flu (both tested) and no cough or significant congestion.