My bsf forced me to touch her

This happened a few months ago and I don't know if it is SA or what it would be considered. I'm 15f and my best friend, who I will not disclose the age of, forced me to do things to her whenever I slept over. She threatened me with a knife and made me finger her and kiss her. This went on for hours and hours.. I didn't get any sleep that night. It still haunts me thinking about it and I can't get over it.