What’s wrong with my baby!

While I was changing my 5 month olds diaper I noticed an odor coming from her. She is my first baby so I’m not sure what to expect from a baby girl. Am I over bathing her? I give her a bath every night. Should I let her air dry? She’s nutramgen for milk allergy and makes her have diarrhea so some gets in her so I always give her a bath to make sure it all gets out. She has her 6 month appointment on the 26th so just wondering what I should do? I’m definitely going to bring it up at her dr appointment

I also should add that there is no redness or irritation also no discharge