Lewington, the club’s longest-serving player, scored twice as the Dons beat Yeovil 5-1 to snatch second spot from Preston on the final day of the season.
“It’s a great feeling, and one that hasn’t sunk in,” defender Lewington told the Citizen.
“It’s a lifetime’s work. From where we started, from the Hockey Stadium days to where we are now. It has been 11 years, and so much has happened off the pitch, so it’s nice to get the stuff going on the pitch.
“We’ve got kids from Milton Keynes coming through the system and that’s what we’re about.
“It was a strange game. We didn’t feel nervous going into it. They’re usually nervy occasions, but the squad was really relaxed. It just felt like it was going to happen.”