I need help

So my daughter had a fever of 102 on Thursday so I took her in and they said she had an ear infection and prescribed amoxicillin. So she took it and was fine on Friday afternoon, then Saturday she had this:

I thought nothing of it, but it was itching her. My dad noticed it and asked me. I thought a tag was irritating her. Then Sunday she looked like this:

So today I took her to the pedi and told him I thought she may have scarlet fever, and he immediately shot me down saying it’s hives. Don’t hives appear larger? This is all over her body and it’s not changing. I thought hives come and go. It is itching her, so I’m not sure.