The Blades were cruising to both victory and the top of the table with just eight minutes remaining after Sharp’s hat-trick had opened up a three-goal lead.
Villa, however, had other ideas and rescued a dramatic point in the fourth minute of stoppage- time.
“We were all gutted at the final whistle,” said Sharp, who took his tally of goals in United colours to 101 with his second hat-trick of the season.
“To be 3-0 up with 10 minutes to go, you are thinking, ‘This is a good night’. It really hurt because we had thrown it away. I still can’t tell you how we came off the pitch without all three points.
“We need to make sure this does not hurt us going forward for the rest of the season.
“We cannot let this hurt us in the games that are coming up. We have to learn from this and respond by winning the next two home games.
“If we do that we look back and see it as a good week with a useful point against Villa. We have to brush ourselves down and go again.”
United host Middlesbrough on Wednesday and then Reading at the weekend.
Sharp added: “The league starts to settle itself out about now. We could have gone top of the league (on Friday), but it was not meant to be.
“For me,the first 82 minutes were the perfect performance. We looked comfortable, were 3-0 up, but then they got a goal and that put their tails up.
“After that they got the ball in the box as much as possible – and got the equaliser with the last kick of the game.
“Now we have to make sure everyone is right for the next game. I am sure there will be changes in these next two games.”