The Shrimpers went ahead midway through the first half when skipper Sean Clohessy fired home from the penalty spot.
But the Dons hit back three times to leave Southend 10th in the npower League Two table, six points below the play-offs.
"We were sloppy and lethargic and I think we got what we deserved - nothing," Sturrock said.
"For the first time this season I would say the players let the club down and they need to look in the mirror at themselves.
"For us to make the play-offs we need to win seven of our remaining nine matches but the galling thing is that there's a good team in there somewhere.
"We've shown it at places like Rotherham, Port Vale, Chesterfield and Cheltenham and we also won at Wycombe and Torquay when they were flying.
"But for whatever reason it just doesn't happen for us at home and we have to get to the bottom of that as we have two must-win matches coming up at Roots Hall against Torquay and Plymouth."