Diaper rash

Please no rude comments, doing the best I can..

My son is two weeks old and has a diaper rash a pretty bad one. It’s been a week. The dr know she told me wipe him with water and baking soda, but it hurt him so I called and they give me prescription cream and it looked better but got worse over last night. I change him often but I can’t seem to get it to go away. Anyone have any ideas on how to help this? I will be soaking him in a warm bath today and letting him go diaperless for a while after to get some air. I use pampers also so I’m open to suggestions on good diapers brands.