The Norwich City winger was part of the England squad which travelled to Israel and came home after the group stage following three defeats.
Since then, the 20-year-old has established himself as a regular in Gareth Southgate’s side during a qualifying campaign which has seen the Three Lions win nine out of their ten games so far.
England U21s v Croatia U21s
UEFA Euro U21 Championship
Play-off first leg
5.45pm, Friday 10 October 2014
Molineux, Wolverhampton Wanderers
Live on BT Sport
Call 0871 222 1877 for tickets
And with Croatia providing the opposition in the play-offs on Friday, Redmond is hoping to help fire England to the Finals in Czech Republic next summer.
"For me, Nat Chalobah, Jack Butland and the other lads still involved, the disappointment still hurts," he revealed.
"It was a very strong group that I thought had a good chance of doing well.
"Unfortunately for us, we didn't do that well but I think personally I had quite a good trip and came back from that tournament with good confidence.
"We got quite bad press, that we didn't really care and that some of the players didn't want to be there but that wasn't the case. I just think that tournament wasn't for us.
"As soon as we got back, we had the friendly against Scotland and it felt like a fresh atmosphere, a new start.
"We knew we had another qualifying campaign to get ready for and that campaign has been successful so far.
"Playing for your country is a big honour for everyone involved, so it's spurred us on and now I want to qualify for these Finals and come up against some of the best teams and win it - I think we've got the talent in the team to go and hurt most teams."
The talent which Redmond refers to is supplemented by a real spirit and unity within the group that has been fostered by boss Gareth Southgate and his staff.
And given that many of the players involved have all come through the same development teams since U16 level and beyond means there is a real sense of togetherness.
"Most of the lads in the Under-21s have been playing together since we were in the U16s and U17s and some of the older boys I know from when I was playing with the U19s," added the former Birmingham City player.
"Once you start mingling with the older age groups, and with the younger age groups, it all just starts to become natural.
"So I've seen players grow from when they were playing for England U16s and they're much better players now, but you know how they play from playing with them four or five years ago.
"We all know what we want to achieve. We all want to pass the ball on the floor, we like to keep the ball.
"We've shown in the qualifying stages we can score goals, we've scored 28, and we know what we're about.
"We know what we've got, we know what we haven't got and if we haven't got it, we make sure that we're working on it to get it.
"Everyone enjoys training, everyone gets along with one another and there's not one lad in the team who's got a massive ego.
"It's not a team full of egos, but neither is it a team full of people who don't believe in themselves.
"It's full of young English players who are performing week in and week out in the Championship or Premier League and we look to bring our form here and fight for our place in the side.
"Because everyone's that competitive, it gives everyone the determination to get to the next level, to say I want to be better than him or he wants to be better than me.
"But at the same time, we're all in it for the same thing.
"Everyone's humble, everyone's hungry, and ready to play in the next two games."
Watch the England Under-21s preparing for Croatia with our slo-mo footage