The home side snatched a controversial last-minute equaliser through Lee Bowyer to draw 1-1 but Ferguson said the goal should have been disallowed.
Controversy: Edwin Van der Sar protests as Lee Bowyer celebrates his late equaliser
The United boss fumed: 'It was a handball and a foul on the centre half. He went right through him. If the referee can't see that what chance have you got? It's terribly harsh. We outplayed them and deserved to win.
'It is a great shame because the way we played in the second half we deserved the three points.
'The first half was a non event but we played ever so well in the second period. Having got in front, we should have finished them off. We just needed a bit more care but their goal should not have stood.'
Bowyer's late strike cancelled out Dimitar Berbatov's opener but the result took United back to the top of the Barclays Premier League.
Ferguson added: 'Am I confident about the title? I think we've got a chance. There's five or six teams are all contesting that area towards the top of the league.
'I always say that if you get to the new year and you're in that top position, then Manchester United have a very good chance.'
Late, late blow: Edwin van der Sar fails to stop Bowyer sliding home the equaliser
Blues boss Alex McLeish admitted his side "got a bit of luck" with Bowyer's goal but was full of praise for their performance. The draw lifted them out of the bottom three and means they have only lost once at home in the last 16 months.
McLeish said: 'I feel that we got our reward for perseverance, good concentration, tactical awareness.
'The players adhered to everything we asked them to do. United had a lot of possession but most of it was deep on the pitch which suited us.
'United cut us open at the start of the second half but we fought back well and got our reward.
'We are not at a safe distance away from the bottom of the table at present but these sort of points could be crucial, bonus points really.'
Breakthrough: Dimitar Berbatov celebrates after giving United the lead early in the second half
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