Day dreams are usually just imaginatory, as in, no actually sights and sounds, just thoughts of them. If you were having a dream then you were definately asleep.

If you said 'no, I'm not dreaming' then it wasn't quiet a lucid. Next time do a reality check, just asking yourself will never work. I like looking at my hands to check, they are usually blurry and not really well defined (like you were looking at them underwater.)