Gareth Southgate’s side were beaten 2-1 at Berlin’s Olympiastadion, leaving the men’s team without a major trophy since triumphing at the 1966 World Cup.
This was their second successive European Championship final loss after they were beaten on penalties by Italy three years ago.
A Cole Palmer strike cancelled out Nico Williams’ opener to give England hope, but that was dashed with four minutes remaining as substitute Mikel Oyarzabal pounced from close range.
“This was another tough moment for the team and for me personally,” Bayern Munich striker Kane told BBC Radio 5 Live.
“Credit to Spain, they played well. We couldn’t find our rhythm in the game and in these big moments you get punished.
“It was a tough tournament physically and mentally. You get so close to the highest of the highs, the pinnacle of our careers, and now everyone is at the lowest of the lows.
“We haven’t found a way to win that trophy and it is going to hurt for a long time.”
Manchester United defender Luke Shaw made a surprise start – his first in four months after a hamstring injury.
He played well in the first half but, like the rest of the England defence, struggled with the pace of Spain’s attacking players in the second period.
“I’m absolutely devastated,” said Shaw. “We really believed we could do it but it wasn’t meant to be.”
Discussing Southgate, Shaw said: “He is extremely proud of the team and what we have achieved as a group but, of course, there isn’t much else he could say. Everyone is truly gutted.
“I think we had massive belief but the fans deserved it. I just want to thank them for their support and can only apologise to them.”
Captain Harry Kane says England’s defeat by Spain in the final of Euro 2024 will “hurt for a long time”.
Kane finished as joint top scorer at Euro 2024 with three goals but the 30-year-old has looked below par throughout the tournament.
He was substituted for Ollie Watkins in the 61st minute on Sunday night after managing just one touch in the opposition box.
Kane missed Bayern Munich’s final game of last season because of a back issue and Southgate admitted that likely played a part in him being unable to deliver his best in Germany.
“Harry has come into the tournament having had an injury at the end of the season and he has played a lot of minutes,” said the England boss.
“He has led the team incredibly well. We’ve lost a lot of leadership in the group with injuries, a lot fell on Harry’s shoulders and he has done exceptionally well.”