Girls, help ?? What could it be? I first thought it was hives, but the…

Girls, help ?? What could it be? I first thought it was hives, but the rash is getting bigger, then I suspected allergy, so I wrote to pediatrician. She said to take Fenistil by 3 drops twice a day. I've been giving it since Friday, September 17th, and this morning woke up and there's even more rash on my neck, lots of pimples and red, and on my cheeks too, with pimples and the skin is really dry, peeling (( We bathe every other day with chamomile, calendula, alternating them all We booked an appointment only for Thursday, but before that time, it suddenly got worse, I'm worried Can you tell me, has