So if we are anxious we notice problems where we may not have done before. If you think this is happening for you, a top tip some people use is to halve the problem you are worrying about, halve it again and then halve it one more time. This is more likely to be the reality you'd perceive if you were feeling your real self.
An example would be: something bad happened at work and the boss invited you to a meeting to discuss. Your mind thinks well, I am going to be sacked....then I won't have a job....no reference....then I won't be able to pay for the family....I will loose the house.... We will have to move....why did I let this happen? I must do more. You work twice as hard, but being distracted its harder, slower, no one seems to be helpful, you notice all the politics.
The reality? It may have been bad, but more often then not it is more likely your manager wants to let you know there is a problem and make sure things are in place formally or informally, so it doesn't happen again (trust me on this after 12years of being in HR). The time, fears and energy worrying about all of the imagined concerns would have been closer to the real situation if halved, halved and halved again.
The importance of not letting negative thoughts escalate is that every time you negatively forecast the future, negative thoughts are converted into anxiety. This builds up more stress and prevents you from dealing with the real problem from your most resourceful, creative and intellectual self.
If you can remain positive in your ability to resolve the problem you can be sure you will be able to get the very best out of the situation... and we all admire those people who remain calm, resourceful and positive when there is a problem and definetely like having them around.