allergy spot

Hi mummies, i just want to check if any have experience this kind of itchy spot on their kids before. My son is 3 years old and never had this issue before. We had went 2 different private doc and poly, and now waiting to see dermatology doc in January. That is the earliest slot we had. The doc from poly told me it is allery spot due to his nose (like something like sinus). Told me it is not something to be worried, but now, it has already spread all over his body and it is really itchy. Currently, we only put some cream Suu Balm on him. I wanted to bring him A&E, but husband claimed that no point, they wouldnt direct to dermatology skin doctor. And expect me to go poly again to request earlier slot, i dont think poly can do that right? Sigh.