Why is my girlfriend getting mad over nothing?

I like to call her princess and beautiful a lot and she gets mad and says im being a fake charmer. We got into a arguement about this today. She said the past guys she delt with would call her endearing names just to get her in the sack and be a player. She's been cheated on in every relationship she says. and she says she can sniff me out in an instant and figure out if im a con. Why is she jumping all over me. I'm not those guys. i'm not gonna change the way i talk or do things for anybody. i have trust issues but im not taking it out on her. I haven't lied to her or hurt her. We've been together for 3 weeks. She has a great sense of humor and thats what i love about her. plus she's beautiful.. but idk why she acting this?! and she got mad cause it took me a while to text back today