Tottenham are on the verge of crisis after their poor start to the Premier League season was followed up with a shock defeat against fourth division Colchester United on Tuesday.
Spurs made 11 changes to their side but there was still room in the team for Eric Dier, Víctor Wanyama, Lucas Moura and Dele Alli, while Christian Eriksen, Son Heung-Min and Erik Lamela came off the bench.
However, they were unable to stop the game ending in a draw and Colchester won on penalties. Eriksen and Moura missed from the spot.
Pochettino said: "Colchester played a fantastic game. We did nearly everything good until the last third. Sometimes you score, sometimes you don't.
"We feel disappointed because we dominated the 90 minutes, but we were not aggressive in the last third in the way you expect. It's about doing your job, and this lack of aggression in the last third made the reality."
The former Espanyol coach added that his squad is "unsettled" and said there are "different agendas" among the players at the moment after last season's run to the Champions League final.
He added: "When you have an unsettled squad always it's difficult and you lose time, then you need time to recover the time you lose.
"That's where we are. Maybe our performances are good but you need this extra, which is mental, connection. It's energy to be all together, not to have different agendas in the squad.
RELATED STORIES
"We are in a period where it's a bit tough for us, but we keep working to find a solution. When this type of thing happens it's about staying clear and fresh and calm. We're trying to find solutions and we only need time."