Unceremoniously 21

I've been told that I'm not the usual 21.
But pray tell me, what does that even mean, who is one? 
The countless depictions, left me confused.
So I formed my own definition, not bothered if it's reused.

I've been accused of maturity, in plentiful.
In deference, pity or spite, of that, I'm still doubtful.
Precocious would do better justice I believe,
As I'm still quite a bit of a fool, by my loved ones' leave!

I've been accused of mirthlessness, unsurprisingly.
I know I don't throw around smiles or cheers ordinarily.
But that does not a man with weary worried lines make.
I do smile inside. Acquaintances! I pause now for your double take!

I've been accused of reticence, by friends old and new.
To this I say, I love to hear more thoughts, and speak but a few.
However, I'm not your internet romanticised introvert, no.
When I want to talk, my taciturnity goes for a toss, as my dear ones know.

I've been led to believe, in this era individuality is treasured,
Then by common standards, why should anyone be measured?
But I'm at peace with myself, so even if you did, there's no harm done.
For in a world still secretly entrapped by dogma, I'm unceremoniously 21.