Does anyone else randomly for a few seconds smell an odd smell if their legs are open but then it goes away? {Better description below}

I am a very clean person I shower and change my panties and I am hygienic person. But every so often if my legs are open and have been open or if they are closed for a bit and I open them I smell an odd smell for a second or 2 then it disappears. Nobody around me ever makes a face or anything when I smell it. I definitely don’t have any STD’s or anything. And this has happened since like 16 and I’m now 21 is it just me worrying or does this happen to other girls.