sleep talking and getting up!!

so whenever i go sleepover at friends houses I always get told that I talk in my sleep or that I will wake up saying random stuff like "im going to beat his ass" or "im moving out" and even walk around then fall back asleep??? I wont remember this when I wake up at all. Like I am never aware that I wake up in the middle of the night and start saying random things!!! Does anyone know what this is??? im scared!!!