my babies breath smells am I the reason?

My son is a week old and I started to notice and odor when breastfeeding. At first it I thought it was by breast pads that needed to be changed causing my nipples to smell. After I showered today and went to feed him again I still noticed the odor and realized it was his mouth/breath. Is this normal? Is my milk causing it? Should it be something to call the dr. About? Any help if you have experienced this would be great!