Talk to Pediatrician on Skin Issue

Aoa,my baby is 10 days old,she have skin issue from day first there was rashes under pamper now its growing up and cover the full body below neck,its seems like red pimples if you want i can send pics pls tel me what its cause and whats your suggestion pls, Moreover baby is normal no weeping or itching complaint but worry for this pimples growing.