Barca were 4-2 up in the first-leg of the Copa semi, only for Atletico to fight back for the 4-4 draw at Montjuic.
Pedri said afterwards: "It's true that it's not the worst result, but when you're 4-2 down, it's difficult to get a draw. It's already happened to us in the League, where we threw it away in the final minutes and we're doing it again.
"We have to learn from these things, especially having the ball, not throwing the line so much, for example. These are things we have to learn, but there's still the return leg to go and we'll go for it."
On going to the Metropolitano for the second-leg, Pedri also said: "It's clear that we're going to go for it. When we're doing well, we're very difficult to beat. The return leg will be difficult because Atlético always puts pressure on, especially at home."