I would go with your heart on this one; that you are concerned you may be a narcissist means you probably are not. I almost always go with the "something else" when I don't like another of the possibilities and see if I can discover what it is for myself and then decide if I mind.

If it were me, I would imagine that thinking and speaking of myself as if I were someone else would mean I did not know or like myself very much so I would set out to see if I could deliberately get to know and like me.

Maybe you can start every morning with writing 10 "I" statements or something? Practice using "I" and thinking "I" and it should get easier. Or, if you like using the third person, figure out what it is that you like about it (it can give a third person perspective so you can more easily see a larger personal picture); I sometimes talk to my body or parts of my body, for example, sometimes even naming them and writing letters to them, etc. to understand them better and what pain or feelings I do not like might be telling me.