The Saints defender had been crossing his fingers for the third home tie on the trot in Paisley but instead the Buddies will travel to the Granite City.
And Dummett is taking belief from the club's last three trips to Pittodrie which have all ended in draws as St Mirren bid to make their first semi-final under Danny Lennon.
The 21-year-old has impressed since arriving on a short-term loan from Newcastle United until January and is desperate to enjoy the Hampden experience.
He said: "You want to test yourself against the best teams and it would have been nice to draw Celtic at home.
"But Aberdeen are going really well and we will have to be at our best to get through up at Pittodrie.
"We've already drawn up there this season and kept a clean sheet while we also drew there in both games last season at Aberdeen, so we can go there knowing that if we get things right we will give ourselves a chance for the semi-finals.
"It would be a dream to play at Hampden and that is a massive motivation to do what I can to help us get past Aberdeen.
"But they are a big club who have made the semi-finals in the last couple of seasons in cup competition and they will be hungry to get their again in front of their fans.
"As a draw it is about as tough as we could have got and it will be up to us to meet that challenge."
Turning to Saturday's SPL game at Perth against St Johnstone, Dummett is determined to take their unbeaten run to three games.
The Buddies left-back said: "St Johnstone will be a big test for us on Saturday.
"They are going well and have put some great results together like beating Celtic but we have back-to-back wins in our last two games over Hamilton Accies and Ross County.
"I think the big plus for us in these games was the way the manager was able to change things up in order to get the win.
"We like to play in the correct manner and pass the ball but sometimes you have to go a bit more direct.
"Last week when we did that with Sam Parkin and Stevie Thompson up top we created real problems for County and it was the same to get the winner against Accies.
"I think that shows the strength in depth we now have at St Mirren.
"But while it is exciting to be in the quarter-final of the League Cup the SPL and making a top-six place our own is our bread and butter."