My GP once told me,
"So you had a bad consultation with one patient. But as soon as the patient walked out the door, you have a very important thing to do - housekeeping. Keep your mind and emotion in check. Take a deep breath, and remember, whoever comes in next, is a new patient. They don't know what happened in the last consultation, they don't know if you messed up with your diagnosis or management plan. They are new to you as you are to them, but only if you do your housekeeping."
Breathe. It's just a bad day, not a bad life.