Thinking about thinking

My mind is chaotic. I'm always over thinking...

Oh brain, why must you over think every single situation?
Thought after thought you seem to leave me where I first started.
Weighing in on every pro and con, missing life as it goes on.
Executing every probability while failing to seize the possibilities. 
Calculating all the outcomes leaves me with a shot not taken.
Statistics occupy my mind while another moment goes by. 
My thoughts and time fly by leaving me to think, always thinking.
All these mental exactions leaving me with what-ifs and no actions.