If she's replacing your name with Hun or Sweetie in normal conversation, I'd say odd are 70/30 its a bad thing. She's placing you below her and toying with you like it is fun. She doesn't take you seriously, nor is she worried about you walking away.
I had a bartender I was flirting with years ago start to call me "Buddy" everytime I came into the bar (I had made a really terrible move to get her out on a date and it came off totally AFC and she wanted to position me as harmless and emasculated).
I politely told her my name and that she should call me that.
I at least held ground, got some respect back, and now when I see her out she's friendly and not standoffish. Of course, I never got a chance to get with her, but I recognized her calling me "Buddy", even if friendly in a bartender sort of way, was not good and I reframed it immediately.
I would recommend you do the same.
"Hey, call me [your name], or from now on you'll be known as "Toots", "Sugar t!ts" or "that Broad"
Say it sort of ****y/funny, with a smirk and not accusatory. She'll respect that and get the message.