Stuart Pearce's squad need to get at least a draw against Serbia on Tuesday night in their second leg to ensure that they reach next summer's European Championships in Israel
Stuart Pearce's side will qualify for next summer's finals if they win or draw against Serbia on Tuesday night, having won the first leg 1-0 at home.
Caulker is determined to help the Young Lions qualify for the tournament and get out of the group stage, which the squad failed to do in 2011.
"I'd made my debut against Germany in a friendly [in November 2010] and I was hoping to go to Denmark, I was in with a shout," the Tottenham defender told the Football Association's official website.
|25/1||Steven Caulker is 25/1 with Bet365 to score first in a win for England Under-21s against Serbia
"But it turned out that injury put paid to it. When I'm injured I always find it hard mentally. I always want to be out there on the pitch and want to be involved.
"It was hard to be out of a big tournament but hopefully we can beat Serbia and I'll get my chance to go to Israel.
"I watched the games in Denmark while I was away on holiday getting some rest. It was unfortunate they didn't get out of the group but I think we can be even stronger next year."
Craig Dawson scored the only goal of the first leg from the penalty spot and Caulker insists that the squad are certain that their slim lead can be kept or, ideally, extended.
"We're confident we can go out there and win again but we'd have loved to have got a few more goals and be a bit more comfortable coming into the game," he admitted. "I thought we did well last game and will look to improve on that too.
"After a lot of clean sheets during the campaign we feel we can keep them out and add one or two more at the other end.
"It's important that we know we have something to defend. Dawson's penalty at Norwich was well-taken and it's given us that one-goal lead and an advantage for the second game."
On the prospect of a penalty shootout, Caulker added: "Dawson has been on fire in training and over the course of the Olympics, he was scoring every day. So fair play to him, he stepped up and hit the back of the net.
"I'm not the most confident penalty-taker but, if you're called upon, you've got to do the job. We practice every day and I'd be happy to [step] forward if it happens."