A season that had promised so much and almost resulted in a Premier League title ended in disappointment for Tottenham, who suffered an embarrassing 5-1 loss to Newcastle in May.
The drubbing meant Tottenham finish third behind Arsenal as the team's bid to finish above their London rivals for the first time since 1995 failed.
Two months on from that woeful display at St. James' Park and Pochettino conceded he struggled to put the performance behind him.
"The feeling after Newcastle was horrible," Pochettino said via the Daily Mail.
"It is true that after a couple of months you move on, but it put me in a bad mood for the whole of the summer. It killed my holidays. Seriously. I went to Barcelona and the Bahamas with my family, but all the time I was in a bad mood.
"There was no time to assimilate the defeat at Newcastle because the season finished at the end of the game and I did not have the chance to share my feelings with my players the day after and kill them!
"Normally when you lose and you are upset with the players you have the opportunity to tell them how you feel on Monday morning when you meet them and have a big discussion and a big fight.
"But after the Newcastle game it was not possible because many of my players went off to the Euros. So I had to keep my bad feeling inside for the whole of the summer.
"Even when I was texting my players in France to wish them well I had to hide my real feelings about the Newcastle game."
Despite the disappointing conclusion to last season, Tottenham are looking forward to Champions League football.
The games are set to come thick and fast for Tottenham but Pochettino sees no reason why his team cannot challenge again domestically in their quest for a first league title since 1961.
"The Champions League demands more energy — physical and mental — and we need to be careful how we manage that and the expectation and the demands,’ he added.
"For me our challenge is to be consistent and consolidate our club in the top. And, is it possible to win the Premier League? Why not? We need to try again, no?"