Wolves couldn't take advantage of Myles Lewis-Skelly's first-half dismissal for the visitors, as Arsenal eventually won 1-0.
Semedo said: “We’re disappointed, obviously. We had a good opportunity to make some points here, especially when we were playing with one more player.
“We had a couple minutes with one more player, so I think we should have taken advantage of that. But even in that period, I think they had more of the ball than us, and then when they equalised, they could score and win the game.
“But in general, I think we did a good game. We did a good job.
“It's what I'm saying. I think we have to be smarter on those points. We will score again, for sure, like we’ve been scoring a lot, but we have to move on.
“I think we did a good game, against a good team as well. Arsenal is a good team, but we had the ball, we created our chances, but we have to move on.
“We have to be working harder, and now we have a full week to work and prepare the next game against us.”