"Fortunato had hurt me a thousand times and I had suffered quietly" I believe that quote is flashback because it speaks of the past.
"Amontillado! Quite impossible." This quote is foreshadowing as Fortunato believes that the drink isn't real at first, not realizing that he is correct until it was too late.
"Yes, let us go" and "Yes, for the love of god!" are both verbal irony used by the narrator. using context around these quotes you can conclude that he is in fact, insane.