Is it normal to sniff your underwear?
Yep.Totally normal
Yes—plenty of people sniff their underwear out of curiosity or to check whether it needs changing. It’s a private, harmless habit as long as you’re comfortable with it.
Totally normal. You might do it to check whether your underwear is fresh, or simply because your own body’s smell is interesting to you. Bodies have smells, and being curious about yours doesn’t mean anything is wrong.