Ok, this might sound weird, but if you made an effort, could you smell any kind of oniony smell? Any discharge? IF so, there might be some kind of infection going on.
If not, either you might not be very hygienic (not that I think that's true but I had to mention it!) or maybe you just ate a lot of onions recently? Seriously, after you eat something strong smelling like onion or garlic, your skin it gonna leak it out a bit. Know what I mean?
Anyway, if that doesn't seem to explain it, I'd see a doc.