BTDT.  It happens commonly when the rivets/screws that are holding the gas
pedal to the floor (just under the carpeting) loosen and the pedal turns a
bit sideways.  Your boot may have had a lot, or a little, to do with it.

Check for sideways wiggleability of the gas pedal and tighten appropriately.

Karl Wolz

I was driving home but after about 5 minutes the gas pedal suddenly would
not depress.

The engine dropped to an idle and I pulled onto a wide shoulder. I got out
and looked at the pedal and found that the push rod (Bentley's 20.31) had
come loose from the underside of the gas pedal. Puzzling.

I snapped it back into place and drove the rest of the way with no further
problem.