Is a serbian film as gross as everyone says?

Im 13 and I watch aot of horror movies (Shining nightmare on elms street) I asked my mom if i could see a serbian film cause i heard it was the scariest grossest film ever and she said if i saw that movie id be grounded for three months?? Wth? What is a serbian film? Ive seen alot of other stuff. Why wont she let me see it? She says its too gross.