The thought I thunked

I thunked a thought, I thunked it once,
then the thunk I thought vanished with a clunk!

I searched the thoughts my  brain had thunk
but all I found was much thunk gunk!

I found a picture of skunk
a memory of gramps and of a chipmunk!
(But no trace of the thought that I did just thunk!)

I checked down low (it might have shrunk)
it wasn’t up on brain’s top bunk.

There I thunked with shoulders hunched:
“your vanishing I must debunk!”

My thoughts went quiet, I heard again a “clunk”
and back to my brain came the thought I thunked!

My brain did add (softly like a monk):
“please take this back, it’s utter junk.

And one more thing:  it’s “thought” not “thunked!”