Speaking as one of the ENEMY" (crewing), then I have just about sussed out when crew are pulling a sickie and when they're genuine.
If it's your ears, then don't even consider working, unless you want weeks off after you damage yr eardrum.
And with a cold, then spreading it about amongst yr colleagues in the air and in the crewroom will mean more work for crewing and more disruption to yr workmates rostas.
Get back to bed !! And thats an order from crewing !