My manager physically assaulted me at work, and I don't know what to do.

I still can't process what happened today. I work as an assistant, and my boss is a very difficult person who always oversteps her boundaries. We had a very normal disagreement about a project, and when I calmly suggested we talk to HR to get a third-party opinion, she completely lost it.

She started pushing her chair into my desk and kept cornering me until I had to stand up and ask her to give me space. I told her I was going to HR, and as I turned to leave the office, she kicked my leg from behind with her foot. I had to stop and tell her again to stay away from me. I'm pretty sure a colleague saw what happened, and the incident occurred in a hallway with a surveillance camera.

HR had already left by the time I finished my shift, so I sent them a detailed email with everything that happened. They said they will start an investigation on Tuesday, and now all I can do is wait. My stomach is in knots from anxiety. Does anyone have any advice on what I should do?