Body odor I can't pinpoint the origin of

[CycloFractal]

Throughout the day, I usually smell the part of my clothes which are closest to my neck and I smell this certain odor. It's rather pungent, smells like onions to me and I get conscious because I think that if it's such a strong odor then other people can probably smell me too. When I ask my mom if she can smell it, she says she can't, and sure enough, if I take off my clothes and smell that part closest to the neck there is no trace of it. I'm really clueless where this smell is coming from, since I can only smell it when I'm wearing clothes.

Thanks in advance for those who can give me any input on this.