Allen was brought to Anfield by former Swans manager Brendan Rodgersover the summer and will face his old side for the first time since leaving on Wednesday.
And, whilst the Wales international admitted it will be a strange feeling to come up against the south Wales club, he is excited about the prospect of facing old friends.
"It is going to be a strange fixture for me and I'm looking forward to coming up against some good friends at a club I was at for many years,” he told Liverpool's official website.
"It will be an interesting game and one I'm looking forward to."
The 22-year-old was delighted to have made his Merseyside derby debut on Sunday, but expressed disappointment over Luis Suarez's incorrectly ruled out late winner.
"It was an exciting encounter and I'm sure that was the same for the fans as well, but it was a shame we didn't get the three points," he continued.
"It was mixed emotions for us at the end. It was a great feeling for a split second because we thought we had won the game, but it wasn't meant to be. Hopefully next time we will get the decision.
"It was a tough and physical battle but we expected that and I enjoyed it. Hopefully this is the first of many derbies I'll experience with Liverpool."