The visitors took the lead after 26 minutes through an unlikely source, as Dean Bowditch’s floated corner saw centre-half Tom Flanagan given the freedom of Meadow Lane to chest down and acrobatically hook a volley in to the top right corner.
The Dons should have doubled their lead straight after half-time but Charlie MacDonald somehow only found Stuart Nelson’s arms from six yards out.
However, County were much livelier in the second period and had their best chance of the game after 53 minutes when Neal Bishop’s superb through-ball fell perfectly for Lee Hughes, but his finish was well saved by David Martin.
County boss Martin Allen and Dons assistant John Gorman were sent to the stands as temperatures boiled over before the Magpies deservedly equalised after 80 minutes.
Adam Smith was harshly adjudged to have handled in the penalty area and Jeff Hughes calmly dispatched the penalty.