I know exactly how you feel. In fact I've had somewhat of gray cloud starting to hover over me on most days for several years now...You just learn to cope with it over time and become apathetic about the feeling. It's not a strong feeling by any means, but an unpleasant, lingering one, and there's no rational reason for it to be there, so you don't exactly understand it, and thus it's near impossible to communicate/express the feeling to other people, as you said.
Big-Boss
Holy fuck, you like the Trailer Park Boys?
GuerrilleroHeroico
Loved the movies