The Finn will start seventh on the grid for tomorrow's race but claims that he would have performed better had a mistake not been made that affected the grip on his Lotus.
Raikkonen said: "I think that we probably should have been third or fourth after this morning and yesterday. But I made a decision to change the car a bit and it was completely the wrong decision.
"It took all the grip away from the car. I'm surprised that we finished seventh.
"I don't think it's going to be the same as it was this morning tomorrow, but we try. That's why I'm very disappointed that I made the decision, because we had a very good car this morning."