"We always play for the shirt and the fans, this is not the result we or they wanted. They should be very mad. We should be mad. Everybody is mad. We are mad. The next game we want to change this. We want to be happy at the end of the game, with smiles on their faces and give the fans a nice weekend afterwards," he told MUTV.
"We definitely don't want to lose two games in a row, so we're going to have to get ready and play much, much better than [on Sunday]. We're not here just to play games and be in the Premier League, we are here to win, we are Manchester United, and that's what we do. We want to win trophies, that's the mentality and the culture of the club. We didn't do it and we are very disappointed.
"There's lots of games still and we have to stay positive, and by staying positive is how we will fight for a good result against Tottenham. That's twice in a row we have lost against [Brighton] here. I think that shouldn't happen. Last year we had almost maybe the same attitude [as Sunday], and it's not right.
"Myself first, should have done much better, less mistakes, control more the game. This was a bad performance for all of us. It's wrong we dropped points. You have to wake up for the next game and definitely not play like we did [against Brighton]."
United have not lost back-to-back Premier League matches since May 2017.