Howe was speaking this morning ahead of their FA Cup fourth round tie against League One Birmingham City on Saturday night.
He said: "It's a great game lined up. Liverpool did what they usually do at Anfield - it was a really good performance from them. Whoever we were going to face was going to be a big task. We really look forward to it but we have to put it bed. That's our challenge.
"We have to (park it). The biggest challenge is to eradicate it from our brain for a matter of time. When you're playing the likes of City, Liverpool in the league and Forest, we can't take our eyes off them. We need to focus on every step before the final."
Asked if he's pictured himself lifting the Cup, Howe said: "No I haven't really thought too deeply on it. I've quickly realised that the size of our task for Saturday, it's a mental task to recover and refocus our energy. We need to see this as a big challenge. I can't live there too long in terms of going somewhere else. It's back to work."
On facing Birmingham, Howe continued: "We'll have to rotate.
"It'll be a difficult ask for players to go again and give the same energy as Wednesday. We don't have a huge squad but we'll try pick a team that is strong enough to win. Those players need to take their opportunities. Any chance they get, they have to take."
On Callum Wilson's return from injury for their Carabao Cup semifinal win against Arsenal in midweek, Howe said: "He seems fine. Callum is very confident about his body at this moment in time. He's gone through several things differently this time around in his recovery. He's trained very hard for this. He feels robust, strong and ready to start games.
"If he can stay fit, he's an outstanding centre-forward. He's got the experienced, the know how, strength, goalscorer. We wouldn't have been able to recruit someone his level who was ready to play."
Along with Wilson, England goalkeeper Nick Pope could also feature tomorrow after returning from injury.
"Nick has shown from his training, you can see he's motivated," added Howe. He wants to make up for lost time. So I think he'll see any opportunity as a chance to remind everyone how good of a goalkeeper he is."
Howe also reflected on Newcastle's quiet winter market.
On keeping hold of Kieran Trippier, the manager said: "No part of us wanted to lose Kieran. He's had a difficult season, a couple of fitness issues that halted his progress. He came back into the team and showed his qualities. To then play and perform in high level is not easy. It's a big skill. He was magnificent (vs Arsenal).
"Tino's (Livramento) had a great season, (Emil) Krafth can play right-back, so there's great competition there."
With Krafth off contract in June, Howe added: "I believe talks are ongoing. He's someone we want to keep."