Jonathan Forte put the Magpies ahead at Spotland but two second-half goals from the hosts gave them the spoils.
"We've had some good chances especially in the second half, but I am really disappointed with the goals we conceded," Sheridan said.
"It's just people making the wrong decision at the wrong time.
"They had a five to 10 minute spell when they got the advantage.
"But I thought we responded really well and created some good opportunities to get back in the game.
"I thought we played well. I don't like losing, but I can take good things from the game."
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