I´m 14 and a freshman at my school. I´m currently dating a junior named Alberto and his parents are both teachers at my school. Her mother, who I am going to call X, overprotects him a lot and is really immature. She always treat me as inferior and tells Alberto I am a bad influence for him, when I am actually a good and calmed student. She scolds me in almost every class, when I am not doing anything wrong and once made me leave last so I would be late for lunch. Alberto tells me she was like that too with his brother´s girlfriend, and treats the situation as funny. I was a little bothered but I could stand it. But today, she was telling the grades of all the class, and told that she wouldn´t tell it to you if you were behaving badly, although it is her obligation to do so. Well, she didn´t tell it to me (when I did nothing wrong) and implied that I got a bad grade. I was thinking about telling the headteacher how unfair she was behaving with me, and I know that if I did that, she would be punished and could even lose her job (my school is kinda weird). I really think X is being immature and that her behaviour is unprofessional, but I know that Alberto would be mad at me if I did that and I would ruin a job in which she have been for years. So Reddit, WIBTA if I told the headteacher about her behaviour?

(Sorry for my bad English, it is not my first language)