Parts of Speech

I am an adjective.
I am happy, I am sad.
I am angry, I am calm.
I am negative, I am positive.
Awake, asleep, crazy, sane, quiet, loud. Absent.
But if I’m an adjective, what noun am I?
Am I the sun, the moon, or the stars?
A tree, a flower, or the grass?
A hero, or a just a human?
Or am I more than one?
One noun for every adjective?
One adjective for every noun?
Or all adjectives for all nouns?
Or no noun at all?
Am I just an adjective?
Do I need to be a noun?
Am I enough of a person to without being just one?
I may not know what everyone else says.
Or what noun I am.
But know I am definitely an adjective.