The result means that the Cherries have now lost all four of their Premier League games this season by an aggregate 8-1 scoreline, a run that leaves them 19th in the league table.
"That was not very good, I've got to be honest. I can't hide it. We were disappointing from start to finish. We've got a lot to work to do," Howe admitted to reporters after the final whistle.
"If you dip in levels you will get punished in the Premier League. We were not good. We have no points, we have to dig deep and find some character and show what we are made of.
"I don't think complacency can be the problem for us. We can't allow that. I take responsibility and I will put it right. I didn't see what I wanted to see today.
"That was nowhere near where we need to be. You can get bad results in the Premier League, but when you don't have performances, that's where concerns creep in. That's where we are. We will lick our wounds.
"We are not creating chances, we are giving up too many chances and we are not passing the ball well."
Next up for the Cherries are back-to-back home encounters with Brighton & Hove Albion, first in the league on Friday ahead of a third-round EFL Cup tie four days later.