i know this so soon after you originally posted, but my dd#2 had pimples all over her face and ears too. I thought it was just heat rash, but the doctor told me it was "baby acne". Im not sure why it wasnt heat rash, because all the symptoms were the same and it lasted a few weeks - just the same as heat rash.
I was devastated when it broke out, but it only lasts a few weeks and once its gone you wont look back!