Having stress at job is inevitable and one cannot run away from work because of rude people. You got this job due to sheer hard work and your own merit; therefore you should not consider things like resigning or changing jobs abruptly just because something happened out of the blue.
- Think about something pleasant such as you taking a long walk in natural surroundings without any human company. Imagine you are walking barefoot on grass in warm sun shining behind a fluff of white clouds. Keep this thought in your mind for 10-15 minutes or till you feel better.
- Go to a time when you were a child and happy with your cousins, family and friends. Relive those memories when you would do nothing significant whole day yet be happy and satisfied.
- Keep a calendar in front of you and turn to a future page. Think if the episode that is bothering you today will still be so effective after one month.
- Make a list of all the achievements in your mind including catching first train on your own to getting your way around in a foreign country. Tell yourself you are a successful person and if you have overcome so many obstacles big and small, you can definitely overcome the present hurdle with some effort.
Finally, do some mantra meditation to immediately calm your frayed nerves. Send that email after you have some control over your emotions. It will help you respond and not react.