Venting

I once was young
And now I'm not.
That knowledge gets
To me a lot.

My hair is thin,
My skin is lined
And if you ask,
Of course I mind!

My knee hurts when
I walk the stairs.
Complaining's useless - 
No one cares.

Forgive my mood - 
It's evident
That there are times
One needs to vent.