The result followed on from a positive pre-season for Jose Mourinho's side and, at the back end of last season, victory in the Europa League to seal Champions League qualification.
Lingard told Sky Sports News: "There's a lot of confidence flying around at the moment and it's good that we can stick together and be a part of it. Even the lads who weren't involved at the weekend still played a big part in the win."
Asked if the mood has changed in the dressing room, Lingard said: "You could say that. We've come off the back of three trophies, so the confidence is flowing. The whole team is working hard this season and hopefully we'll win trophies. We're in a lot of competitions, the more trophies the better."
Lingard, who came through the ranks at United, has made 85 senior appearances for the club since his debut in 2013.