They could have tied things up at the death as Will Addison saw the ball dislodged as he dived for the line by a desperate Paul Hodgson tackle but Redpath felt that his side should have been out of sight by then.
He said: "I'm bitterly disappointed - I certainly thought we had enough possession and territory to win the game by ten points. I thought it was a game we should have won.
"The facts are that we didn't and, in the ten minutes after half-time, we were poor in a couple of exits which allowed Worcester a bit of field position.
"Then, late on in the game, I thought the officials got it wrong as there were about eight penalties in a row and two of them were definitely professional and I think people should be punished for that.
"A yellow card would have allowed us a bit more dominance around the set-pieces, but we got no advantage in the end.
"We had a chance to score, but although it was a good tackle in the corner, I think we should have scored and given ourselves a chance to level the game."
On the back of two comfortable Amlin Cup wins, Worcester did not look at their most fluent, and even though they stretched to an eight-point half-time lead, they never looked in complete control.
Warriors' Director of Rugby Richard Hill admitted that there was room for improvement but having lost a lot of tight games already this season he could not hide his relief at only a second Premiership success of the campaign.
He said: "I think we looked rusty and that is always a problem when you come off the back of two Amlin Challenge Cup games when you've won by 80 and 90 points and haven't really been tested.
"Sale had Heineken Cup games against Cardiff and Montpellier, so were a bit more battle-hardened than we were.
"Our lineout work and game-management was rusty - in the Amlin Cup, we just ran everything, so didn't have to worry about kicking and that needed looking at. We played quite a lot of rugby in our own half and caused quite a few problems for ourselves.
"We weren't at our best by any means, but we showed a lot of spirit to repel Sale at the end. With all the pressure they had in our 22, they probably deserved more than just one point from the game."
Sale Sharks' next Aviva Premiership battle is at home to London Irish next Friday, 2nd November, kick off 8.00pm. Buy your tickets online.