In "The Pit and the Pendulum," what happened to the narrator at the end of the first paragraph?

At the end of the first
paragraph, the narrator swoons.  

If you are like my students,
they do not immediately know what "swoon" means. It means to faint, to lose
consciousness, to pass out, and/or to black out.  

The reader does not know
for sure that the narrator has lost consciousness until the reader reads the first sentence of
the second paragraph.  At the start of that paragraph, the narrator flat out announces that he
"had swooned."

Swooning does carry a slightly differentthan a
simple passing out.  When a person swoons, it is often because of an emotional overload.  Having
the narrator swoon at the end of the first paragraph makes perfect sense, because the narrator
has just been sentenced to death.  From the moment that his death sentence is pronounced, the
narrator starts to lose touch with reality.  He admits that he no longer hears specific
words. 

The sentence -- the dread sentence of death -- was
the last of distinct accentuation which reached my ears. After that, the sound of the
inquisitorial voices seemed merged in one dreamy indeterminate hum.

By the end of the paragraph, the narrator is hallucinating and
wishing for death. 

And then there stole into my fancy,
like a rich musical note, the thought of what sweet rest there must be in the grave.

His mind simply can't handle everything that is going on, so he
swoons.