my question to native speakers:
can one say "to be in the spot" meaning to be in a (tight) spot where we use definite article because the spot was mentioned in the song before so it is not "a spot" anymore? just wondering...Although I doubt it myself as this is a fixed expression...
In that case, I'd say "in that spot" realizing that it would be become a bit of a play on words because, as you say, it's a fixed expression.
I'm really in a tight spot here!
And how did you come to find yourself in that spot?