Just Not Funny Anymore

Yesterday, I was laughing at something very simple
Enjoying the moment and making light of it
Then suddenly you get hit by something
And now the world becomes upside down
You see things differently
Good becomes bad
White becomes black
Confusion
Wasn't that good yesterday?
Why is it black now?
To turn it around, you go back to your roots
Your training
Your experience
The people you trust
Then you realize what's wrong
So you stand up
And turn it around
Confusion again but it's shorter
Then everything settles down
But how come it's not funny anymore?