The Royals are six points adrift of safety following Saturday's disappointing defeat to Southampton.
Shorey admits their below-par display against Southampton concerns him and he accepts they need to improve if they are to climb clear of trouble.
"It concerns me a lot. There's not a lot else you can say it concerns me we're down there but we've got to man up and make sure our performances get to the level they need to be because they haven't been," said Shorey.
"We've shown in games we've got the quality and we can score goals but we've got to do it for 90 minutes.
"We feel like we can get something out of every game but not with second half performances like [against Southampton]. Hopefully it'll come. We all know we need to up our game and show a bit more on the ball because it's what this league demands."
Reading face fellow strugglers Sunderland on Tuesday and Shorey admits the players need to rally together to end their slump in form.
"[Sunderland] will be thinking it's a good time to play Reading. That's just the way it is.
"We're both down there and it's a big game for them and big game for us. Spending money doesn't always get you where you want to be and we need to pull together as a group.
"New players always bring new enthusiasm and will make the players here buck their ideas up a bit and try and push on as well and hopefully we will add a few but we don't need to go silly. The lads have shown we're capable at times."
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