Oh yeah, I do that too! I've been doing it as a conscious effort towards a positive self-talk, like when people tell me I look good or something I reply "I know, thanks" instead of the usual knee-jerk reaction of completely disregarding them and possibly even denying it verbally, for about three-four years now, essentially as a "fake it till you make it" kind of an attitude towards self-confidence. And I too have been struggling with this, the thought of "am I being narcissistic?" when I dare feel anything but burning hatred towards myself and my own well-being. Herein lies a distinction, the important difference between 1) having narcissistic traits (which, like it or not, everyone - including you, because you aren't that special to be completely devoid of them - has) and 2) having these traits in so much of an excess that it could and would be diagnosed as narcissistic personality disorder (which is rare, like 1% of population can be diagnosed).

I trust the sentiment that /u/Clent (btw does Lemmy work like this?) below said, that "No narcissist has ever asked themselves if they are being narcissistic". People who suffer from this personality disorder don't work like that. Also judging by what you bring forward here I really wouldn't worry about it; usually people who call other people "narcissistic" when said person is acting "selfishly" (with a stark contrast to the complete anti-self acting previously exhibited) don't know what they are talking about.

But of course it is good to look in a mirror every once and a while, especially regarding how you act towards other people. I have been diagnosed with borderline personality disorder, which is in the same cluster of personality disorders as narcissistic and also anti-social personality disorders, and I can recognize in myself the tendency to act without judgement towards my own actions. Beforehand, that is, hindsight is always 20/20 though. But usually these actions tell me that I am in dire distress, and need help urgently. Your mileage may vary.