The duo impressed the panel on this weekend's episode with a Flintstones-themed routine, which involved Pudsey standing up on his hind legs and 'dancing' with the teenager.
Speaking to Digital Spy, Butler said that she felt extra pressure to impress given Simon Cowell's well-established love of dog acts.
"I've been watching Britain's Got Talent since the first series and there have been some amazing dancing dogs on there," she said. "I've just been thinking 'How can me and Pudsey be different from that and [do] stuff that's not really been done by a dog before?'
"Everyone knows that Simon likes a good dog act and even though that's a good thing, it could also mean if he doesn't like us, we could be letting down the dog side of Britain's Got Talent.
"In my eyes it was a bit of a risk, but a good risk. Even if he didn't perform to his best I wanted people to know that he can still do it. But on the day he didn't put a paw wrong."
However, Butler said that she was unsure if she would take up Cowell's suggestion of giving Pudsey his own costume due to her concerns about the dog's well-being.
"He would look cute in a costume, but I want to make sure Pudsey feels comfortable when he's performing," she said. "Wearing a costume might just affect his performance, so [it] might be a bit of a problem."
Butler also stressed just how much "hard work" is needed to put their act together, though she said her priority is making sure that Pudsey always has fun.
"It does take a lot of hard work and I want people to realise that," she said. "But also Pudsey loves doing it. He loves performing and me teaching him new tricks. It's all about making sure Pudsey's enjoying it and having as much fun as possible.
"When you think of Britain's Got Talent you think of singers and dancers, but also the dog acts. And I want [people] to realise a lot of hard work goes into it. Singers and dancers, we're just as good as them."
Britain's Got Talent continues Saturday (April 14) at 8pm on ITV1.
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