i reincarnated in to my Novel

i was just a normal guy who wrote the novel called I got reincarnated in to a magical world, and became pretty popular. but one day when i was writing my Finale chapter someone broke in to my house and killed me, and when i woke up i was confused at first but then i realized i was reincarnated in to my own novel, and to top it off there was 4 new characters that i didn't create. and btw the reason i wrote this novel is because i want some experience before i write my main novel, which will be 10 time's better than this one, of done right.