What am I?

I can be many things, but I am just one thing

I am stuck
Lost with myself
Although I know I am here
Racing at 100 miles per hour
When it comes to being put out
I feel empty
Insignificant
I become nothing
Although I know I am something
From experience to imagination
I am there
But I am not there when there is time
I put myself in stories
In hypothesis, theories, music
I am creative
Yet in the now I say nothing
I am silent
Powerful
Truly unforgiving
I am words