The defender signed permanently from Bournemouth over the summer.
Mings told BirminghamLive: "I'm not young but I'm playing again, but I needed to establish myself as a centre-back. Maybe as a Premier League centre-back it was getting a bit late. I went to the Championship and played well, but people said, 'Yes, but that was in the Championship'. I needed games.
"It's been nine months since I came to Villa, before Christmas I was playing in the 23s games, Premier League Cup, I think the biggest lesson I can take out it - and hindsight is a wonderful thing - is that no matter how trapped, or out of control you feel your current situation is, there's always another path you can take, but at the time I couldn't see that path.
"I knew that coming to Villa, things had to go well, because my career was in danger of slipping away. I'd been out of the spotlight for so long that I needed run of games to show people what I could do."