Have No Idea WHAT Is Going On

(I’m working at the jewellery counter as a Christmas seasonal employee. I see a display is looking a bit sparse so while I’m not helping anyone I grab some jewellery from the storage drawers under the display to refill it. My manager passes behind me and sees the empty display.)

Manager: “[My Name], refill the jewellery display if you aren’t doing anything.”

Me: “I’m already on it.”

Manager: “What?”

Me: *wondering if I offended her by my wording* “What?”

Manager: “What?”

Me: *stares at the manager, completely confused*

Manager: *to another worker* “I never let anyone say ‘what’ to me. Not even my own daughter.” *walks away*

Me: *flabbergasted*