Donyell Malen struck twice in the first-half that eventually saw Villa win 2-1 on Thursday night.
“I thought we controlled the game well,” Lindelöf said.
“Towards the end, I think we were a little bit sloppy with the ball, we lost the ball quite easily a few times, and after the goal they got a little bit of energy and tried to get the equaliser.
“That’s something we can’t allow. We have to keep focused for 90 minutes and make sure we end the game.
“If you score a third goal, that’s game over and their energy can drop a little bit and we can control it a little bit better.
“I think we can be a little bit more ruthless and try to score a third goal and make it easier for ourselves.
“But if you look at the game, I think we controlled most of it, and deserved the three points.”
On his first months with Villa, the summer arrival from Manchester United added: “I’m very, very happy.
“All of the guys and everyone working around the club have welcomes be in the best way.
“I’m super, super happy and thrilled to be a part of this club. I’m trying to do my best and help the club and the players every single day.”