Tiago Cukur netted his first senior goal to give bottom side Doncaster a much-needed win over high-flying MK Dons, four days after they lost 6-0 at Ipswich.
Tommy Rowe put Rovers ahead early in the game only for Peter Kioso to equalise before the break in an even contest at the Keepmoat Stadium.
“When you suffer a defeat like that, it gets you down,” said Wellens. “You can lose football matches, but the manner of it was very disappointing.
“But even on the coach on the way back, straight away the whole group was thinking how can we get a result on Saturday?
“Everyone involved at the club, through Thursday and Friday it was all positive, with really good messages and really good training sessions.
“I thought our shape was really good today. Out of possession against them, if you’re not good they’ll cut you open.
“We are two months into our project and they are two or three years into theirs.
“They had a really good season under Russell Martin. He recruited very well in the summer and you only have to look at the subs that came on to see that.
“The new manager has taken it over and integrated his own ideas. I think they’re a really good football team.
“For us to go head to head with one of the more stabilised outfits in the league is a real positive.”
Doncaster Rovers: Dahlberg, Knoyle, Anderson, Ro-Shaun Williams, Rowe, Close, Bostock (Smith 68), Galbraith, Hiwula, Dodoo (Cukur 77), Vilca (Barlow 46).Unused substitutes: Jones, Seaman, Gardner, Horton.
Milton Keynes Dons: Fisher, O’Hora, Darling, Lewington, Kioso, O’Riley, Robson, Harvie, Twine (Boateng 78), Parrott, Watters (Eisa 67). Unused substitutes: Watson, Jules, Kasumu, McEachran ,Ravizzoli.
Referee: A Kitchen (England).