Rash everywhere

Hi everyone hope u and your babies r doing well

So , my baby started to have this weird red spots everywhere early today it started in her abdomen and spread to the back and now her whole body is covered with these spots and its spreading to quick

Does any one knows what it might be, Note that I didn’t give her any new food or used new thing for her

Please help I’m scheduling her appointment tomorrow but I can’t just set here not knowing 😭😭😭