Michael Symes' header ended the Mariners' three-game unbeaten run but Newell immediately switched his focus to Monday's game at Notts County.
He said: "It's a frustrating day for us and there is a bit of nervousness around the place. But it's still in our hands with four games to go. We have a big game at Notts County on Monday now and then next week against Port Vale.
"If we can get back to the performances of recent weeks then we have a great chance in those next two games.
"I would have settled for a point. It's not the result we wanted but we weren't at our best and I would probably have been happy with 0-0.
"At home of late, we have been dominant but for one reason or another we weren't at the races and didn't create any clear cut chances until the second half."