Sounds like the Overgeneralization cognitive distortion:
In this cognitive distortion, a person comes to a general conclusion based on a single incident or a single piece of evidence. If something bad happens just once, they expect it to happen over and over again. A person may see a single, unpleasant event as part of a never-ending pattern of defeat.
Very true. Why do those of us afflicted with Anxiety disorders think like this? Probably because we're genetically predisposed to think that way in some cases. I am, that's why I pursued an Engineering career-my brain was genetically optimized to be strong in problem solving. Problem is, the same mental strengths which are an advantage in my career work against me in my private life. I have to learn to 'turn them off' when away from work. And what makes that difficult is the second reason for GAD-many of us were raised in families with a lot of continual tension and anxiousness. So, not only is the 'hardwiring' faulty, the 'software' is faulty as well. We have the old double-whammy, which makes addressing GAD doubly hard.
But, it can be done. 'All things be ready if our minds make it so!' Henry V, by William Shakespeare
We must be careful what we put out into the Universe.
You can call good stuff or bad stuff upon yourself. Positive or negative,
For instance, everyday say, 'I am a good person and I deserve this job'
Understand that if you don't get said job it was not meant to be.
Also understanding that in the end you will get a job.
It's a state of mind. You can strengthen it. It is yours.
Hope this helps.