Your CEL's P0011 and POO21 are linked to sensors., Variable Timing
solenoid, O2 sensors are some to name a few that throw that code on an
OBD reader. You may want to pay a diagnostic fee to an Infiniti dealer /mechanic with an infiniti specific tool to see the exact codes:
With those codes the first thing that comes to mind is low oil level...
Have you checked the oil level? This may be the problem…did you have the codes before or after the oil change?
If before oil change, it could have been low on oil prior to oil change
If after just clear then the codes by disconnecting the negative battery for 10 minutes
I have also read to always use OEM parts like NGK plugs since this engine is known to be sensitive to any aftermarket parts. also, it seems that is very common for after market Cam Sensors to Cause P0011 or P0021 codes if the oil level is ok.