Graham Alexander admitted Fleetwood Town had thrown away results as their season ended in a fourth consecutive defeat.
Victory ensured the Dons survived the drop, a goal from Gary Alexander and a Jack Midson penalty doing for Town.
“We’ve been naive,” admitted Alexander. “We’ve conceded two poor goals which has been the story of our last 10 games. We’ve thrown away results.
“I don’t think there was anything in the game. It probably could have been a 0-0 or 1-1 draw, but we’ve just ended up giving silly free-kicks away through a lack of discipline and then the penalty.
“ I didn’t see it clearly but we’ve given them an opportunity to win one and that’s the big thing.”
Both of Wimbledon’s goals came from set-pieces – a disappointment for Alexander, who was left to question his side’s second-half discipline.
The winner came after Rob Atkinson had bundled over Curtis Osano, angering Alexander, who added: “I don’t think it was a definite penalty, but it was an opportunity to give a penalty and that’s what I’m annoyed about.
“I don’t begrudge the result but the referee was swayed by the crowd. He gave a few free-kicks second half when the crowd played a big part.
“We spoke about it at half- time –not letting that happen, not giving the chances.
“You have to be disciplined and we didn’t do that in the second half. The effort was there but we’ve got to get the results.”
Town looked low on confidence against the fired-up Dons but Alexander believes the problems run deeper.
He said: “It’s more than just a confidence issue. It’s been a step up in level to where they are now.
“Some people have made that step and some haven’t.
“There’s been a change of manager. It’s taken time to get to know everyone and for them to get to know me.
“A lot of things have added up. We’ll go into the summer, do the work that’s needed and get the squad that can compete at this level.”