Mike Phelan decried Hull City's bad fortune after a "cruel" 82nd-minute own goal handed a 1-0 victory to Watford in the Premier League on Saturday.
Hull's defence had held firm for most of the game after an early Watford onslaught before Dawson diverted Nordin Amrabat's cross into his own net.
The Tigers have now lost six consecutive Premier League games and remain in the relegation zone.
Phelan conceded the nature of Watford's winner meant the defeat was a particularly sour one.
"It's very hard to take, I have got a depressed dressing room after the work they put into the game," Phelan told BBC Sport.
"The winning goal is a cruel one, it's flashed across the box and hit someone on the leg and gone in.
"It could have gone anywhere. If it is a worldie then you can hold your hands up."
Watford struck the woodwork twice in the opening 10 minutes, but Hull grew into the contest and Abel Hernandez should have done better with a chance early in the second half.
"We were competitive enough in the game, we created probably the best chances in the game, but were are on the end of another defeat," Phelan said.
"We have to react to that and I am sure we will do next week.
"Everyone has to weigh in with goals and, at the moment, it is not happening."
