For the visit of one of this season's fancied sides , the Dons continued in a 3-4-3 formation, with Richard Butler fit after taking a late knock in the FA Cup win at Ashford.
Worthing made the early running, with centre forward Stafford Browne prominent, without threatening Andy Little in the home goal.
The first threat on Little as he defended the goal in front of the West Bank came on 5 minutes when Danny Davis gathered a half cleared corner but shot just over.
Worthing striker Richard Pacquette should have opened the scoring on 12 minutes when he turned his man in the area but sent a poor shot wide.
The Dons were slow in finding their feet, with Sonny Farr lively wide left, but a tame header from Micky Woolner was all that resulted.
On 17 minutes the Dons fell behind when ex Dons youth teamer Marc Cable powered home a header from Liam Collins' corner.
Steve Butler was close to finding an immediate equaliser, but Worthing keeper Mark Ormerod was equal to his header from Barry Moore's freekick.
Rather like the Withdean side that dominated the Dons' first CCL season, Worthing were matching brain with brawn and dominating the midfield exchanges.
Worthing could have gone further ahead on the half hour as Pacquette's shot rebounded off Little, but Stafford Browne could only stab the rebound wide.
Captain Butler again went closest to to an equalizer on 31 minutes, as Ormerod could only flap at Farr's corner and Butler headed Shane Smeltz's cross over.
Smeltz himself finally awoke the Dons faithful soon after when he met Wes Daly's cross with a flying header, which beat the keeper only to rebound off the crossbar.
As half time approached, Smeltz tried to break the lethargy around Kingsmeadow but his half volley from Moore's corner cleared the angle of post and bar.
The visitors reached the interval ahead by a single goal, their tactics of consistently leaving 9 men behind the ball paying off thus far.
Both sides had to alter things at half time, with Steve Butler replaced by Mark Cooper and the combatative Grice replaced by Rogers for Worthing.
The Dons appeared to revert to a 4-4-2 formation, but the game seemed to revert to a pattern of Dons possession but little penetration. Worthing meanwhile seemed happy to play on the break and looked capable of adding a second at their leisure.
The first chance for Worthing in the second period came on 65 minutes, when sub Sam Francis set Collins clear, but he dragged his effort well wide.
Attacking the West Bank finally awoke the Dons and Moore had the Don' best effort on 68 minutes when Ormerod tipped his shot over at full stretch.
On the break Worthing continued to threaten, but a combination of Cooper and Dave Sargent managed to foil a mazy run from Francis.
The Dons' frustration continued as sub Jeff Campbell sent a looping header wide with Ormerod beaten and Woolner sent a weak effort straight to the keeper.
Finally the Dons got their deserved equalizer as Jeff Campbell was felled and Barry Moored crashed home the resulting freekick off the bar in the 77th minute.
Having seemingly settled for a point, Worthing grabbed an unlikely late goal as Francis was allowed too much time and space inside the area to scramble the ball in.
Alas for the second home game running the Dons conceded a last minute goal, which this time saw them slip to to their first defeat of the season.