studiovette

I took my stock Automatic 07 C6 with 18k miles out this past weekend and noticed when I either floored the gas pedal my RPM's shot up and then when I released the pedal the Rpm's would just hover around 3k and then fall off a cliff. Is that normal? The same thing happens when I apply half the pedal down off the line. This has been happening as of late but was very noticeable yesterday. It kinda feels like the car is not up/down shifting properly when the pedal is released. Could it be that I need to have injectors cleaned or transmission checked?
Has anyone experienced this b4?
I've only had the car for a year and only put 3k miles on it since getting it. The car sits in my garage allot and when driven its just local cruising which could be part of the problem. I only use 93/94 octane Mobil/ BP/Sunoco gas

Any recommendations or suggestions would be grealty appreciated.