Ferguson gave Everton credit for turning the game at Goodison Park on its head after the champions had controlled the first 45 minutes.
He said: "It was a battle, but Everton turned it into a battle in the second half. Their crowd were up for it and in fairness you have to give them credit because they unsettled us and we started to give the ball away and that's cost us the match."
Ferguson also took Wayne Rooney off after he had been booked for a collision with Mikel Arteta, then angered the crowd at his former club by kissing the badge on his United shirt.
But Ferguson felt the blame lay with referee Wiley again, saying: "The referee was to blame, and the crowd was egging him on and there was every chance he may have been sent off, and not for anything he did in the game.
"You get a booking for nothing and then you wonder what the referee is going to do next.
"Cristiano Ronaldo had a chance near the end if he could have dug it out of his feet, but we didn't deserve anything because at that point it was a hanging-on job."
Everton boss David Moyes, in contrast, was delighted with how his side responded after being outclassed in the first half.
He said: "I was actually a bit disappointed we didn't win the game in the second half, but drawing with Manchester United at the present time is a good result for us.
"Fellaini has done well for us. He's only a 20-year-old boy and he has come into a side that has not been playing well. He is one for the future and I have no doubts he will be a star for us in years to come.
"I won't lie, if you had said to me before the game would I take a draw I would have said yes and I'm pleased with the way we played in the second half."
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.