The world number two went down 6-4 7-6 (7-5) 4-6 7-6 (7-5) to Seppi on Friday, bringing his bid for an 18th Grand Slam title to a grinding halt.
Speaking after the match, Federer conceded that he had not been feeling great in the build-up to the match, but that the unease was normal.
"I felt for some reason yesterday and this morning it was not going to be very simple today," he said. "Even in practice I still felt the same," he explained.
"This is a feeling I've had for 15 years," added the Swiss superstar.
"To me, I don't read anything into that. It's just not the best feeling to have.
"It's not like I'm playing shocking or I'm feeling shocking. It's like one of those things you look back and maybe think, 'Yeah, I didn't feel so good'.
"But if you win, you never even question it. If I were you, I wouldn't read very much into that."