The Magpies appeared to be heading in the right direction after collecting two wins during a three-match unbeaten run, but have since tumbled down the Premier League standings after suffering back-to-back defeats.
Their latest setback came on Monday, with a dismal first-half showing leaving Alan Pardew's side with a mountain to climb against Everton.
They did respond after the break to haul themselves back into the game, but still went down 3-2 and pockets of the away support were quick to air their displeasure at Goodison Park.
Williamson, who was introduced off the bench on Merseyside, told the Evening Chronicle on Newcastle's struggles: "All I can say is that we're equally, if not more, disappointed than them.
"We're frustrated. We want to get back on the training pitch and put it right.
"The fans can see it and the players are the same, we're striving to find that consistency and balance.
"We have fantastic players. We struggled, but Everton are a fantastic team with a fantastic manager. They are still unbeaten, which says a lot."
Williamson, who could be drafted back into Pardew's starting XI for Saturday's trip to Cardiff City, added: "It is a big club. There is plenty of competition for places. It is up to the manager to pick the team.
"I am sure he will pick the 11 players and bench that will be suitable for Cardiff.
"Most of the lads just let their football do the talking."