The Coventry keeper played a crucial role in Sweden's 1-1 draw with Argentina which clinched first place in Group F and ensured that the South Americans were eliminated.
"Nobody expected us to get a point from the Group of Death and we have gone on and won it," said a delighted Hedman.
Hedman saved a penalty from Ariel Ortega before Hernan Crespo knocked in the rebound on 88 minutes.
It's the best thing that's happened to me in my career
Sweden scorer Anders Svensson
"We are full of confidence and we know that we can compete with and maybe beat all of the teams left in the competition."
Sweden coach Lars Lagerback hailed his players' teamwork for their success in the tournament so far.
"We have a special group of players who are very team orientated, all working so hard for each other," he said.
"We knew we would have to defend well and we did. It's fantastic to finish top of the group."
Goalscorer Anders Svensson admitted he could hardly believe it when his second half free-kick beat Argentina Pablo Cavallero.
"It's the best thing that's happened to me in my career," the Swedish midfielder said.
"When I saw the ball go in I went crazy. It's fantastic. Everybody played well, the whole team."
"It was a great experience to play against a team of Argentina's calibre - to come up with a draw is fantastic."