help!!

Okay so my boyfriends nephew has been diagnosed with scabies. My 7 week old has had a rash on her arm and leg for about a week now doctors have said it's probably baby acne. But now I'm freaking out that she might have scabies!! Shes around said nephew frequently and her rash/acne has been getting worse despite the creme that was prescribed. Should I take her to the doctor and ask for scabies treatment for her and myself? I really don't know what to do!!!