Nicki Minaj was reportedly none too happy at last night's Fashion Rocks concert, and she didn't keep quiet about it!

According to concert insiders, the singer was raging that she didn't as much rehearsal time as fellow diva Jennifer Lopez.

J-Lo "ran through her song twice because the stage crew needed some extra practice for her scenery set-up,” a concert insider said. “Then Nicki wanted extra rehearsal time, too, even though production didn’t need it.”

When she was refused, Nicki apparently had a total temper tantrum. "She was acting completely out of control, and threatened to walk off the show," the source revealed.

Nicki made a few snide comments on social media too. She took to Instagram to say, "Artists spend so much of their own money, time and passion to deliver their fans great performances. But ultimately, our art usually falls into the hands of people who care nothing about our art and creativity" – this in relation to the fact that the cameras missed some of her best choreography.

"CBS decided not to show it," she said. "Had they told us this before, we would have changed the choreo[graphy] so that you guys could see the full performance from beginning to end." Ouch! 

She also posted this message on Twitter, mouthing off about how her performance of Anaconda was filmed:

Offstage at the awards, Nicki showed off an unusually demure look, with natural slicked-back hair and a black dress:

It seems the toned-out down outfit didn't match her temper though!