I have seem many quotes about the fact that we often can't change the things that are happening around us, but we can choose our internal reactions to them. As time has gone on and I have experienced this for myself, I have come to believe that it's true and I really love this notion!
Anxietyuk.org.uk defines internal and external stress as follows:
"External stressors are sources of stress that we are aware of around us, these can include traumas, life experiences or simply daily hassles. Internal stressors are the sources of stress that are inside us and are often the most common sources of stress. They are the thoughts and feelings that pop into your head and cause you to feel unease, these can include unrealistic expectations, uncertainties, low self esteem and apprehensions".
We all experience stress, sometimes double stress. We experience something such as a tight work deadline that's a cause of stress, then we can keep going over how annoying and unfair it is in our mind, perhaps doubting our own ability to complete it etc, creating secondary sources of stress.
By being aware of this concept we can start to separate the stress and understand where it's coming from and potentially do something about it. Do you need to calm your nerves? Perhaps you need to take a moment to slow your breathing down and re-focus to complete the task in hand? Do you set high expectations that would require more time that you actually have?
I can definitely relate to the stressful internal dialogue around situations that have, are and might happen. But by creating some space and awareness between me and my thoughts, I can often identify that these doubts, worries and fears are simply thoughts and not reality, which don't need attention paying to, lowering my stress levels considerably.