Help identify rash!

Blaire

7 month old has had this rash on the side of her butt for about a week. Look familiar to anyone? I'm a super rashy person (allergic to Band-Aids and perfumes, both me and my older daughter have eczema). But I don't recognize this one. Obviously can't take her to the doctor for at least 2 more days so I'm hoping there's something I can put on it at home. Thoughts?