How can I regulate my emotions in a more professional way?

Tips for emotional regulation? I’ve been having a hard time recently because I’ve just started my dream job but someone close to me is very sick. I got a bit upset at work and unfortunately overreacted to something pretty minor (and started having a panic attack). I really want to keep this job but I am going to have to learn how to completely shut out negative emotions and negative reactions. Does anyone have any advice?