Amoxicillin rash??

My daughter has been on amoxicillin for 2 days now for tonsillitis. I noticed yesterday she had a rash on the back of her neck. I spoke to my pharmacist and he said it's unlikely to be a reaction to the antibiotics but to keep an eye on it. This morning it has spread to her chest and forehead. It doesn't look angry or bad but I'm not sure whether to stop giving her the medication or if this is normal? I can't get hold of my doctors this morning!