Analysis of My Train of Thought

I lost my train of thought today.
I don't know where it went.
At first, my train was on its way
Expressing what I meant.

I thought I saw it hug the tracks
When going 'round the curve.
That's why I never could relax
From what I did observe!

When out of sight, the whistle blew;
I hope the engineer
Was merely testing what was new
Upon the train this year.

My thought apparently derailed;
Attention was not paid.
My daydreaming is why I failed.
So much for plans well laid!