Scared first time mommy

I noticed this on my baby’s face today and I don’t know what it could be. It’s cold outside so it can’t be a heat rash. It’s bumpy and small. She isn’t fussy so I don’t think it bothers her.

Melina is only 3 weeks old and I’m a first time mom so I’m paranoid about everything.

My little brother is in love with her and keeps on kissing her and I’ve been reading a lot of posts about not kissing babies I don’t know if this is a case of allergy? She is exclusively breastfed either bottle or boob so she isn’t having an allergic reaction to formula.

Please help! Her doctor can’t see her until Monday.