Sheldon struck his second goal of the season in first-half stoppage time with a smart finish from the edge of the box after latching on to Iyseden Christie's brave flick on.
It was the first time Harriers had scored the first goal in a game at Aggborough all season and they went on to hold on to their advantage relatively comfortably.
High-flying Morecambe slipped to their fifth Conference away defeat of the season with goalkeeper John Danby's excellent first-half save from Jim Bentley being the only real bright spot for the Shrimps.
With veteran Martin O'Connor influential in mid field and former Exeter man Sheldon an energetic performer up front, Harriers enjoyed more of the possession.
Centre-halves Daryl Burgess and Mark Jackson did a great job of keeping Morecambe top scorer Michael Twiss quiet to claim Kidderminster's first home clean sheet of the campaign, ending a run of three straight defeats at Aggborough.
Although the hosts were the better side in the early stages in front of 1,461 fans, their lowest crowd of the season, the first half rapidly degenerated into a scrappy affair.
Bentley was twice close with headers, especially when Danby denied the defender with a sprawling stop on 36 minutes.
But Sheldon gave warning of his menace with two efforts flying across the face of goal before he tucked away the Harriers opener in time for the interval.
Although Danby claimed a Wayne Curtis long-range drive on 76 minutes, Harriers looked the more likely to grab a second goal.
Chances were largely at a premium, but Morecambe goalkeeper Ryan Robinson plunged to his left to prevent Michael Blackwood from finding the net on the hour mark.
However, Robinson was grateful to the post 12 minutes later when Christie, racing on to Sheldon's superb through ball, cut inside to smash his shot against the woodwork.