Do trolls give police threats and they're not serious about it?

I saw that a troll said that she will commit suicide but she also said "brb" and she said it sarcastically and her "friend" said that she will call the cops on me because that troll "committed suicide". The troll's "friend" kept saying mean things to me like saying she attacked my mom and whatnot. I have a feeling that the troll's "friend" isn't serious but I'm scared that she called the cops on me. I didn't start the fight, the troll and her "friend" did and they were playing victim. What I'm asking is if trolls just use police threats to scare their victims. Do they? Do trolls say that they called the cops just to scare users but they didn't actually called the cops?