Pools fell behind when Ben Garrity was able to scramble the ball in from close range just after the half hour.
The goal came during what was perhaps Pools’ best spell in the game but meant Sweeney’s side were chasing from then on.
While Pools remained competitive until second half stoppage time, Lucas Covolan was rarely troubled in the Port Vale goal before Tom Pett doubled the Valiants’ lead to seal all three points.
“I feel like I’m repeating myself. I’m a little bit of a broken record at the moment,” said Sweeney.
“We didn’t create enough in the attacking third and then conceded two really poor goals again.”
Sweeney made two changes to the side which lost at Swindon Town in midweek with Edward Jones and Luke Hendrie replacing Reagan Ogle and Zaine Francis-Angol as Pools also altered their shape to a back four.
“We wanted to come here and try to frustrate and be compact, but we conceded a really sloppy first goal which changes the direction of the game. It was a body blow.
“The first first goal in games for us is very important. Very rarely do we concede first to then go on and get points from the game or potentially win the game. When we score first we pick up a high percentage of points.
“It’s something we’ve spoken about for months. If our away form isn’t good we’ve got to find a way to be resilient and stay in games.”