And after a poor showing in Saturday's 1-0 loss to Brentford, Cooper conceded that the pressure is getting to him.
He said: "We lacked quality, and the boys could have been mentally stronger when we had possession of the ball.
"But I have said lately that if I can't do it, then it's time for me to move over and let someone else come in.
"I'm frustrated at the moment, and it's hard when you see the effort that is put in. But saying that, we need better quality in front of goal."