Rangers have been stuck in the relegation places since the start of the season and replaced manager Mark Hughes with Harry Redknapp in November.
Hughes, who was only appointed last January, signed 12 players during his short reign, and Derry reckons the influx destabilised the squad who had won promotion from the Championship under Neil Warnock.
Derry said: "At times it's hard to take because you feel that you get the club into the Premier League and you want to be part of it. You want to play.
"The teams that got promoted in the same year as us, Swansea and Norwich, they seem to have done things a lot slower than what we have at QPR - rightly or wrongly.
"I hope we can get out of the problems we're in at the minute. I can only speak from a personal opinion - things should have been done a bit slower really.
"I suppose when you get the opportunity to bring in these guys who are at the top of the profession - Mark Hughes, who was our manager in the close season, thought we should be bringing in a number of players to enhance our chances of progressing.
"It just didn't work out that way. It takes time to mould a team, it really does. My own opinion is things were done just too quickly."
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