He said: "When I was sent off it didn't hit home straight away what games I would miss.
"It was in the dressing room shortly afterwards when I was on my own that the consequences hit home.
"I went through a number of emotions, including self-pity because I really wanted to play in that game, then I felt sorry for my family as they all had tickets for the match and then I felt annoyed and disappointed with myself for what had happened.
"The club appealed against the sending off but as there was no video evidence of the incident it was a long-shot to get it overturned and I had resigned myself to the fact I would not be playing."
Although Torpey won't be taking part in the game, he will be helping keep the younger members of the squad calm - and is still hopeful of getting to play against a top side later in his career.
He added: "We have quite a young squad and for some of them this could be the biggest game they ever play in so the excitement is building and everyone is looking forward to it.
"I think I've still got a couple of years left playing in me yet so you never know what will happen in the future and who you get drawn against.
"I've had some good games in my career, I played against Tottenham at White Hart Lane when I was at Millwall and I played for Swansea in the play-off final at Wembley in 1997 when we were beaten by Northampton.
"They were big games but I think it would be fair to say this game would have been the biggest. I'm sure though that everyone connected with the club will have a great day out."