Mauro Icardi cancelled out the Hirving Lozano opener and a win here would’ve put them through to the Round of 16, as Barcelona held Tottenham to a 1-1 draw.
“We were unable to keep our calm, despite the fact everything was still possible. We gave the ball away, were tactically not organised and PSV were allowed some dangerous counter-attacks,” Spalletti told Sky Sport Italia.
“As the anxiety grows, you lose sight of how to control the game and it became end to end. We had our chances to score, but it wasn’t the right attitude we needed in that moment.
“Not every team can beat anyone. This does weigh on our psychology and we had to keep the game in the balance, but we became too frenetic after going a goal behind.”
Barcelona were leading Tottenham Hotspur at Camp Nou, until an 85th-minute Lucas Moura equaliser.
“Naturally, the crowd cheers and the players look around to see what happened. UEFA asked if I wanted to have the results from elsewhere pop up on the screen and I said yes. A team like Inter needs the mental strength to handle that situation.
“It’s not one player who can change the overall attitude of a team, it’s a much bigger picture. We must do everything together, as it’s the only play to play like a unit.
“It’s easy to look back and say there are moments when we could’ve done better, but once again we let the tension get to us and didn’t handle the situation well.
“There is disappointment, the same as any other club that goes out of the Champions League.”