its not unknown for cabin crew to panic, this is one of my favourites
There is always a chance that a percentage of humans will panic when fear overtakes their experience.
Much more common for untrained passengers and hopefully pretty damn rare for the crew flying the aircraft (aviate-navigate-communicate will focus your mind)).
Hopefully when one of the cabin crew cops it, a more calming influence will emerger from another cabin staff member. I can't be surprised by an occasional FA showing panic and certainly not the passengers, but somewhere there needs to be the shout downs from those with their wits still about them.