I'm not sure. I think the speaking without really thinking about it can be a normal thing. You'd have to talk more in depth with a professional...

There are some very "normal" forms of dissociation most everyone utilizes on a daily basis. Driving on "autopilot" to get to familiar places, daydreaming at school or work, "zoning out" during a boring meeting, etc are all very common forms that don't necessarily interfere with life and are not necessarily a cause for concern... dissociation generally occurs on a continuum,from relatively mild (stuff like driving on autopilot) to severe (like dissociative identity disorder). Speaking without thinking about it might fall at the mild end. More concerning might be speaking without thinking about it but also being shocked at what comes out, as if it were not something you would normally think/say or believe,and not intending to lie or be contrary.