The cause for your baby's condition can be either Eczema
or monilial spots or just a sensitive skin.
It is too early to start any medications on her as she is just 7 weeks old.
Please hold on for some time.
My advice for you is use a very mild water to bath her, it is advisable not to use any soap or soap lotion on her now. Give her bath with just plain water.
Use Johnson and Johnson baby oil to moisturizer her skin.
Wait until she is 1 year old to go ahead with the diagnosis and management of her present condition.
She should be fine soon.