Marcus Tavernier admitted mixed emotions after Bournemouth's 4-3 defeat at Leeds United.
Tavernier struck his first Premier League goal on the day.
He said, "I am gutted. I think everyone in there feels it. It happened last week, it happened again this week. We have a two-goal cushion and have given a multiple amount of goals away. It is unacceptable. We can't keep doing this as teams at this level will punish us.
"The staff and us will look at it over the week and pinpoint what we need to do. At the moment we are giving away too many goals."
On scoring his first Premier League goal, he added: "It is a bittersweet moment. I am happy to get my first goal in this league but I am disappointed in the result and that overshadows it. Everyone is devastated. Nobody is talking [in the changing room]. We are letting ourselves down too much.
"We have to concentrate on clean sheets and defending better. We will be doing a lot of defensive work in the week to keep the ball out of the net."