*Uh oh, someone pushed Keri Hilson’s buttons. Last week in Las Vegas, the singer supposedly had a “diva moment” after a performance at Haze nightclub. She was just finishing up when she realized her harem pants hadn’t been removed. She got back stage and went off on her assistant.

A source said, “Hilson lost it. She was screaming at her assistant for ‘not being able to do anything right.’ [She] railed that the assistant also forgot to ‘pack her eyedrops and throat spray.’”

But her assistant wasn’t going to accept that. She responded with, “Oh, hell no!”

The two nearly got into a physical fight, but security came out and broke the two apart before it all went down. That was the end of it.

Only part of the story was confirmed by Keri’s reps who said she did ask her assistant for eyedrops and throat spray because she was feeling under the weather, but there was no altercation. They denied it never got to the point where things boiled over.

She’s had the same road crew since day one.