Is it fine to email my supervisor of any concerns?

I work in a hospital, but only per diem and every other weekend. I work as an aide. It's going to be my 4th month and my 90 probationary period is over. There's going to be a big meeting coming up with all the aides and I overheard that the supervisor was going to go over major things. I heard from another aide that something happened last week with misunderstanding between a nurse and it led to one patient just leaving and disappearing because that aide was supposed to watch. They were supposedly going to fire that aide, but didn't. The problem is I was the only aide that worked in that certain floor that happened, and it was worrying me because I had no clue this had ever happened but I was the only aide that worked that week in that floor. I was about to email my supervisor and just ask her if I am doing a good job and if there's anything I can work on. Is that okay to ask?