This is happening to me too but my problem is that the bad smell is coming through my nose other known as nose breath. my parents can't smell it but everyone else can. I try to hide my face but my parents say why you covering your face. And so then the other people that smell it cover their nose or rub there nose. And it's embarrassing that I go to middle school so it's not very easy trying to ignore the problem. I am trying to have my parents take me to te ears,throat, and nose doctor. Maybe you should check with them.