That doesn't seem normal to me. I think the vet is your best bet for this. Is she on a puppy food? I would use a good oatmeal shampoo...something very mild and gentle. Make sure you're rinsing ridiculously thoroughly. That's all I can think of other than something to do with vaccines. No sign of thinning anywhere else? Any scratching? Well...maybe the vet will have some answers for you. Let us know. I'll be thinking of you and hoping you get some good answers. She's adorbs btw.
Properly trained, a man can be dog's best friend.
"If you love wealth better than liberty, the tranquility of servitude better than the animating contest of freedom, go home from us in peace. We ask not your counsels or arms. Crouch down and lick the hands which feed you. May your chains set lightly upon you and may posterity forget that ye were our countrymen." -- Samuel Adams 1776