My manager made me so mad

So I work in the ED and I’m orienting a baby nurse (only been on the floor for 5 weeks). We had a crazy assignment, we finally got a break to have lunch. I sent my orient to lunch and I sat down at the nursing station to eat because we don’t get real breaks. In the room next to the nursing station they were coding someone. I saw that there were plenty of people in the room so I sat down and ate my lunch. My orient came back and asked if she could go in the code and do compressions. I told her yes and continued to eat my salad.

My manager asked me to go to her office later and she told me that she saw my orient “alone in the code”. I guess I should have gone in there with her but I just wanted to finish my lunch. Also, there were so many people in that room. She told me that she was able to squeeze in there and basically said I missed a learning opportunity. I find this insulting because despite not getting paid for orienting, I try to teach my orients everything. Also, even though my orient isn’t taking critical care or trauma patients yet, I still take her into traumas and critical care assignments to expose her to as much as I can. I don’t like being told I’m not doing enough while taking my break at the nursing station. What are your thoughts? Should I have gone in there or told her don’t go in there without me?? Or do you think she was fine with 3 other nurses and 3 techs?