Newborn skin

Hello all, my baby is 4 weeks today. She has this rash/ skin issue on her neck and face. I’m not too sure what it is… I thought maybe heat rash or allergic reaction ? I use Johnson shampoo on her head and body wash on body and her body is free of anything sort of rash. I use Johnson lotion on her body and started using aquaphor on her face to try and relieve some of the rash, just because it feels rough in some areas. Do you all have any idea what my baby is experiencing? And any sort of remedy? Also maybe she has sensitive skin, what body washes/ lotions would you recommend? Thank you in advance!