I don't understand what it is, temperature for 4 days and only today 3…

I don't understand what it is, temperature for 4 days and only today 37.5 and I have been having rashes on my stomach and back. The first few days the temperature was 38-39 and they say there isn't a fever at all, but we have both fever and rash. But the child eats, plays and in general feels good. We took a test and now waiting for the pediatrician's answer. Look at the photo, maybe someone else has had this too.