underarms rashes/ bacterial infection

Hi, in week 10 all of a sudden i experienced severe itchning in both underarms, and my armpits went dark pink. This continued for a few days and then i started noticing some grey skin in between the pink with fine white powdery formation. I dont use very many products, no deos etc, and have been trying to cold wipe the area everytime it itches. I havent had any such problems in the past. Here are some pictures. My ob appointment is next week. Attaching pictures for help here in the mean time. Is this anything to worry or will it go away with general hygiene.