"I couldn't sleep properly, I'm not Superman, I'm the way I am and I can deal with that," he said ahead of Tuesday's match.
Brazil coach Tite admitted on Monday he's been having sleepless nights ahead of the Copa America semi-final against Argentina.
Tite took over from the sacked Dunga following Brazil's poor performance at the 2016 Centenario Copa America and said that he is just as nervous now as he was during his early matches in charge of the national team.
"I couldn't sleep properly, I'm not Superman, I'm the way I am and I can deal with that," he said ahead of Tuesday's match in Belo Horizonte's Mineirao stadium, the scene of Brazil's 7-1 semi-final humiliation against Germany at the 2014 World Cup.
"Yesterday I woke up at 3.15 am, I was thinking about what I'm going to do.
"As a coach I always have a notepad next to me to write something down. That's the reality of being a coach, not just me, (Argentina coach Lionel) Scaloni too, all of us."
This match has been billed as a clash between the individual brilliance of Argentina's star players such as Lionel Messi and Sergio Aguero against the collective ability of Brazil.
But Tite said the Argentina team is more than just a collection of individuals and that it would be impossible to try to just stop those singular talents.
"Argentina make the most of those individual talents linking them into a coherent unit," he said.
"You can't eliminate Messi, you might be able to reduce what he can do but you can't neutralize a player of that level, just as you can't neutralize (Philippe) Coutinho, (Roberto) Firmino, Willian, David (Neres) -- at some point, they will produce something."
In goalkeeper Alisson, Brazil have one player who is used to knocking Messi out of important competitions.
He was in goal in 2017/18 when Roma came back from a 4-1 Champions League first leg deficit against Messi's Barcelona to win 3-0 at Rome's Stadio Olimpico and reach the semi-finals on away goals.