Calafiori had a chance to win the game in injury-time, but his header was saved by Sunderland goalkeeper Robin Roefs.
“I didn’t know if I wanted to make an assist or to shoot on goal because the goalkeeper was coming really close to me. At the end Mikel (Merino) was also there, so I don’t know, it’s a matter of actions," he said afterwards.
“I think you can see we are really, really disappointed, especially because we came back. I really liked our reaction in the second half. I think we deserved (the win) and we dominated the game. At the end, for a matter of a duel or one action, we lost some points here.
“(Manager Mikel Arteta) just said that we needed to basically win our duels and then from there we could start to play our game, so that’s what we did. I think you would have seen on the pitch in the second half, I think we deserved it, we played better than them and just in one action you concede, and you draw the game, but this is the level.”
Sunderland's goals were the first conceded by Arsenal in nine games.
“I’m so happy to be part of this team, this defensive line,” Calafiori added. “Whoever plays, I think we do really good, but I don’t really care about the record, I just want to win every game and try to concede as least as possible.
“We are top of the league so we must be happy at least, we need to think about that. We need to think about the next game which will be tough, and actually many games that will be tough in the next few months, so we are fully focused and I’m proud of my team so far.”