When you feel as though you are going to get upset go into a room by yourself and sit down calmly and quietly. Keep something that means a lot to you at hand close your eyes and focus on it. Think of all the good things in your life or if not a favourite film. Take deep breathes and relax.
The best way is to share with someone whom you feel comfortable with , possibly with your friends, speak out to them what you feel, like the reason behind your emotions and i bet you for sure you will feel a bit more relaxed.
Donot overact or imagine about your problem.Try to be quite.Sit in a place and go on think how you can overcome this.Just ignore it.Dream as thugh you are king/queen and punish the creators of the event.Sit and plan how to get help to escape.