"The team has been a bit of a shambles," Antonio told The Footballer's Football Podcast.
"Last three games, three losses, we've not really been performing at all. We've been a bit all over the place. It's not the standard we set from the beginning of the season. I just take it as a bit of a slump. Hopefully we can come back from it in the next couple of games.
"I can't really put it down to Everton. They played well. I just don't think we performed well enough. I don't think we kept the ball well enough, when we had the ball we kept giving it away. Our performances have been slack over the last week."
Antonio, 33, has not found the net since 26 August and has two goals to his name this season.
His Footballer's Football Podcast companion Callum Wilson has seven for Newcastle.
In a bid to find more goals, Antonio has thrown down a goalscoring challenge and hopes to make up ground and deliver a bigger tally than Wilson by the end of the season.
Antonio added: "I need something. Let's go for it. I need something to push me now."
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