What could this be??

The sitter sent me this while I’m at work. My daughter just recovered from an allergic reaction. I was giving her Benadryl & an oral steroid for it. Now this pops up.. is this from allergic reaction or bug bite? Anything I can do or should I be worried? She has a doctor appointment tomorrow & was wondering if I should wait or take her to urgent care. She doesn’t have any other symptoms other than itching it