There are many definitions of a reference and a reference to school. But what about a reprimand (Saxony)?
My teacher told me that he had applied for a headmaster expulsion because I dragged a folder with a little game onto a laptop (but only for the break). But I also have the feeling that he just doesn't really like me. Is that reason enough for a headmaster to be expelled? I almost got one a year ago, but was able to prevent it. That's why I think that's why it's more critical now. What are the chances that the current one will be enforced and what are the consequences?
If it was a school laptop and you played during your school days, you're due!
If it was your own laptop, then it wasn't. You can have what you want on private devices!
You also write that you have the impression that your teacher doesn't like you! A counter question, what are you doing in class so that he could have a good opinion of you?