The way she whipped that thing out like she was drawing a glock, there are only two possibilities.
a. She did it on purpose for what ever reason and was prepared.
b. If it was real, then it happens so often that she is more than used to it.
But I do agree that if she gets a clear message that she is going to get squashed by Bernie, she would likely withdraw rather than suffer another defeat.
That's the kind of person she is. A person of no character or ethics, with an undeserved, unearned, monumentally over-sized, ego.