Goals from Adebayo Akinfenwa and Scott Kashket gave the Chairboys all three points as Michael O'Connor and Akinfenwa saw red at Meadow Lane.
"It’s disappointing to lose the game," said Sheridan. "I'm a bit disappointed myself in the way it’s ended up. We’re struggling to keep clean sheets at the moment.
"I actually thought in the first half we started the game well. But the goal comes - they’ve had a little half chance before it - but the goal comes out of the blue.
"It’s just basic defending. You can see the cross coming in and it just puts a downer on all the effort we’ve just put in to start the game well. I think the fans appreciate we started the game well."
"We’ve had attempts at goal, and we’ve had little good areas, but their goalkeeper hasn’t really had to save anything which, again, is a downer for us.
"We’re the home team, we expect him to be making saves and we created one or two opportunities but again we haven’t worked the goalkeeper," he added.
The defeat meant Notts have taken seven points from a possible 33 at home - a statistic the manager wants to change as soon as possible.
He said: "Poor home form is something I’ve never experienced myself as a manager in whatever club I’ve been at.
"My home form’s usually good so it’s a big concern for me and it’s a big concern for the club. That stat is just not good enough.
"I expect a lot more from us when we’re playing at home and expect us to win games and expect us to have more possession, score more goals and we’re just not doing it."