
The Hammers are expected to challenge for promotion back to the top flight following their relegation in May, but have taken only one point from their first two matches.
Having squandered a 2-0 lead in their opening game to draw at Burnley, their first home league match of the campaign ended in a 2-1 defeat by Charlton - with Taty Castellanos missing a stoppage-time penalty.
Asked whether he personally feels under pressure because of their relegation last season, Nuno said: "It's West Ham, the pressure is every day.
"This is the more disappointing feeling."
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Published1 day agoLloyd Jones struck Charlton's seventh-minute opener after West Ham allowed a long throw-in to bounce inside their penalty area and Tyreece Campbell put Charlton 2-0 ahead when Konstantinos Mavropanos was dispossessed near his own penalty area after the break.
"We created a lot of situations but we weren't accurate enough in the boxes," said former Wolves and Nottingham Forest boss Nuno, speaking after his team had more than 77% of possession and finished on an expected goals total of 2.96 to Charlton's 0.57.
"We have to defend much better. We had a lot of possession and tried to break them down, which is not easy.
"We were still able to create a lot of situations that we should - and will, for sure in the future - finish better.
"This season, it's clear that we're going to be protagonists and will have more of the ball. We [will work on] combinations in the final third and in one-on-ones, creating situations that can allow us to score.
"We're going to repeat, repeat, repeat - but keep the belief in the process. We're going to get together and bounce back."
West Ham's next match is a Carabao Cup tie against Southampton on Tuesday, with league matches against unbeaten duo Watford and Wolves to follow.
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