Is this heat rash?

Yeah most likely it’s heat rash. It’s quite normal especially the first month. Is there breastmilk available? If yes, you may have a milk bath for your LO. Wipe your LO’s head with a clean wash cloth dipped in cooled boiled water and make sure the environment is not too warm. Wear loose clothings underneath swaddle. It will go away on its own, within a week or two. Sometimes in a few days.