The Aggborough outfit were undone by Phil Trainer's third minute header and a wickedly deflected Chris Blackburn goal, both of which came from poor defending at corners.
Inbetween those strikes, Anthony Malbon had pulled a one back but while Harriers saw plenty of the ball, they struggled to open up Telford's defence.
"We huffed and puffed and I thought the winning goal summed up how things are with us because I thought we were on top," said Burr.
"You give people jobs to do at corners for and against and they're not doing them at the moment.
"Their other goal was fortunate because it took a deflection and went in, but when Anthony Malbon scored I thought we would kick on.
"The second goal knocked us back at bit and you've got to make your own luck at times and we didn't do enough of that.
"We're not getting the rub of the green at the moment but that's something you have to make happen yourselves.
"A bit of confidence has gone when you're not winning but we're disappointed when you give people jobs to do and they're not carrying them out and it's costing us.
"To concede how we did tonight was unbelievable, especially the first goal."
Defeat means with nine games left, eighth-placed Harriers are seven points behind fifth-placed York in the Blue Square Bet Premier.