I used to think I was conscious, but then I realized I was mistaken.

Dennett actually believes somehting like that about phenomenal consciousness.

[Dennett:] These additions are perfectly real, but they are … not made of figment, but made of judgment. There is nothing more to phenomenology than that [Otto:] But there seems to be! [Dennett:] Exactly! There seems to be phenomenology. That's a fact that the heterophenomenologist enthusiastically concedes. But it does not follow from this undeniable, universally attested fact thatth ere really is phenomenology. This is the crux. (Dennett, 1991, p. 366)