8 Week Old Infant With Scalp Rash

hello i am looking to chat with a pediatrician .. My 8 week old infant developed a red hot looking rash on her scalp. She has no other symptoms and is both bottle and breast fed. Her rash appears to have small bumps and seems worse when she cries. Her complexion is otherwise perfect. The face , abdomen , legs, arms, back, and diaper area are totally unaffected. i should note that she does not seem to be uncomfortable. Any clues? Kate