Is it legal to videotape at work?

I am a room attendant and one of my colleagues come in to the room I cleaned and got upset because I told her to change the hoover bag if it’s full. She took it very personal and got in my face shouting and pushed me. I immediately start recording a video and show to my manager. She said I’m not allowed to videotape at work. Can I videotape someone else if I feel threatened?