How to get myself into the Christmas spirit?

I'm 15 years old and i'm just not feeling it, i'm not excited at all. Christmas is tomorrow and I want to get in the spirit before it's too late. My house has decorations, I have a tree wih plenty of presents under it, there's snow outside and everything. I dont know why but I'm just not excited like I have been for the first 14 years of my life. Any help? Thank you and happy holidays!