Screwed Up at Work and Can’t Get Passed It

I got super frustrated at work and publicly lashed out. That is not who I usually am at all, but work has been so difficult lately. I care a lot about doing a good job. I have a meeting with my boss, who I’ve never really had to deal with in a negative way before but know from coworkers who have that she is volatile. I intend to apologize and be mature and make amends any way I can, but I can’t stop fixating on the situation.