Grows within me

There seems to be something odd,
A twitch of a branch, and indentation in the sod;
A little double-take,
Make sure I am awake.

Another day, normal occurrence,
My brain rewires, and gives me assurance;
A month goes by, maybe two,
And the world is back to its blessed hue.

But there it is again! An eye-rubbing what?
Something that's kindred to reality's shortcut;
It's instability,
Now daily grows within me.