Jonjo Shelvey's labelled his dismissal against Tottenham Hotspur as a "moment of madness".
The Newcastle United midfielder was sent off for stamping on Dele Alli in the club's season-opening game.
Shelvey – who hopes to play against his former club Liverpool at St James's Park on Sunday – went on to serve a three-game ban.
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"It's obviously been frustrating, because it was a moment of madness," said Shelvey. "You try to put it to the back of your head.
"You just get people chatting a load of rubbish about you, to be honest. You don't listen to them.
"With the media side of the game, they'll hammer you when you're doing something bad and try to be your mate when you've done something right.
"You never forget who's said what."
Shelvey had impressed in pre-season after working through the summer on his fitness.
And the England international had to "plead" with manager Rafa Benitez to play in an Under-23 fixture after serving his suspension.
Shelvey – who has been kept out of the team in recent weeks by the form of loan signing Mikel Merino – came off the bench in last weekend's 1-0 Premier League defeat to Brighton and Hove Albion.
"I had a very good pre-season," said the 25-year-old.
"I was very fit and sharp, and that happened. It's just been stop-start. Credit to the lads, they've come in and done really well.
"It's obviously frustrating not playing. You want to play every minute of every game, but I've had to wait my chance.
"I came on and did OK the other day. I want to get a start under my belt for the minutes.
"I dropped down and asked the gaffer if I could play in the Under-23s, and he was a bit like 'no, I don't really want you to play', and then I pleaded with him to let me get some minutes. It has helped me.
"It's just been stop-start and I want to get it going and show the fans what I can do, because I let them down on the first game of the season and I let my team-mates and the manager down.
"It's time to repay the fans, my team-mates and the manager."
Shelvey – who was widely criticised for the stamp on Alli – has refused to speak to the media since his dismissal against Tottenham.
"You can learn from anything in the game," Shelvey told NUFC TV. "I couldn't tell you to this day what I was doing. It was just a moment of madness, an error, that I've apologised for.
"I've not come out and said anything. I've not done an interview.
"The only people I will apologise to is my team-mates, my manager and the fans. I'll not apologise to anybody else outside of this club. It's nothing to do with them.
"They can print what they want and do what they want."