People generally see me as insecure and narcissistic/cocky.
Given my social persona I totally see how they arrive that conclusion, but it's only that, my persona.
Since I'm unconfrontational paired with a live and let live attitude most people won't ever get a glimpse as to what is behind said mask. If I take something seriously I generally finish what I started. That is what confidence means to me, making decisions and sticking by them - it's mostly that I hardly ever take anything seriously enough to attach myself to it.
Still, questioning too much can easily lower one's self-esteem, at least if it is oneself you're questioning. Not because analysis is bad per se, but because eventually you'll run into a rabbit hole with no escape, nor answers - and if you cannot find any answers you remain in a confused state of mind which only feeds your insecurity.
Been there quite often, I'm certain I will again - generally however I've learned to accept certain things for what they are, rather than trying to dive into a one way street of demise and distress. Still, the goal isn't to practice ignorance is bliss - but if it ain't hurting anyone including yourself there's no reason to dwell too much in it.
Most people just need to make themselves feel better about themselves by putting others down and/or needing affirmation. The whole pseudo-confidence hogwash is nothing but bullying inevitably. There are confident people, few and far inbetween - you however immediately notice the difference as they possess an entirely different way / aura. Contentedness has no vile intentions and for as long as people are being malicious/bitter there isn't any true confidence to be found.
Being extremely small-minded and unwilling to see alternative perspective seems to lead to aggression for most folks (I prefer the term butthurt) - it is then considered to be normal, or confidence, as they stand by what they think. At least that is the impression I am getting when people use the term confidence.
As for me, I consider myself quite humble as it were, occasionally I must remind myself to not make it a virtue as that will skew my perspective as it triggers a mindset of superiority which I find harmful. Additionally I found that many attacks from others can be re-directed at them easily, as they're exhibiting what they're criticizing you for - this makes me wonder if most things in that regard aren't mere projections of people's own insecurities.
EDIT: A little anecdote;
The other day I wrote with a stranger - given that I like writing using fancy words and hilarious sentence structures paired with a whole of bunch irony/sarcasm the recipient turned onto me and called me attention seeking, pseudo-intelligent, validation seeker, narcissistic and lonely. All because of they way I typed. Now my question is as follows: Why do people feel threatened by such things?
It is quite revealing and a lesson worthwhile learning and applying - whenever you feel threatened by anything, ask yourself why you are. Chances are there is no valid reason most of the time (irrational insecurity) - as such this helps building confidence tremendously if as a result you can turn off a harmful perception of things where there shouldn't be any to begin with.
Helps for a more positive outlook, too.