baby rash or eczema pic include

my son is 4 months old and has eczema. I've tried J&J;, and Dove soap. his 4 month check up was Wednesday and I told his doctor about it and she said to try aquaphor soap and lotion. She gave me samples of aquaphor soap and Venicream. I've been using the venicream lotion since Wednesday and have not seen his skin rash up. today I took him a bath with aquaphor and he broke out like this. or could it be the detergent from the washcloth? I told know what to do?