Job interview in a company offering gas heaters

I don^t know about you but I have always had problems with stress. I don^t know how to deal with it and it is something that I have to work on. It is a serious problem when you think of it and I want you to be aware of this fact. Do you know how to deal with stress? For me some situations in life are full of stress and they are driving me crazy. I don^t know what to do and how to overcome them. Let me give you an example of a situation in which the stress has been overwhelming and I couldn^t fight it. For the last time I have felt it during the job interview for the company offering gas heaters. I have been in stress and I didn^t know what to say during that job interview. I have been shocked that they have contacted me later as I thought that I have lost my chance. I have been wrong. Eventually they have called me and I have received this job but I still can^t understand why. In my opinion it was the worst job interview ever and I am ashamed of it. I hope that in the future I will learn how to cope with stress and that situations like this with a company offering gas heaters won^t happen again. Tell me what do you think about it as well as leave a comment with your opinion about stress. Thanks in advance for your contribution.