"On numerous occasions we got to the byline, got the ball into the box and we just wanted it to go in, but on another day we would have had three or four," he told MUTV.
"Their goals were a deflection and one of those that comes out of the blue with a long-range screamer, but it's obviously disappointing to lose when you have created so many chances.
"To lose two defenders (Jonny Evans and Phil Jones) in the way we did, after so many players came back to fitness, is also disappointing, but after we got that goal early in the second half I thought we would go on to win. It was not meant to be, and there is a lot of disappointment in the dressing room."
United are currently seventh in the league table with 40 points from 24 matches.