The former Newcastle United fullback couldn't find a club for much of last season.
"At the end of the day everything is a bonus for me now after the time I spent out of the game," reflected Carr to the Birmingham Mail. "At the time, I couldn't get a club. That's just life, isn't it? If no-one wants you, you just go to the gym and get on with it.
"People did say to me 'why have you retired?' and I'd say I couldn't get a club. They would say surely I could, but I couldn't. They don't realised football has changed now. Whereas before if you came out of the Premier League, if you contract was up or something, a lot of players would be guaranteed something in the Championship before.
"But now the money is getting scarce in the Championship and clubs wants to spend it wisely, which you can understand, with older players and especially full-backs. If you're a forward then they think maybe because you can always nick a goal you could be massive for the club.
"But I don't think the number one priority is a full-back. That probably didn't help me. But now, just to have got the opportunity to play again, it's been brilliant. As for the future, who knows."