what doesn’t help is the way that everything on the web

 This actually triggers the release of stress hormones at certain times of day. That’s because stress hormones are one of the tools that the body uses to wake itself up when you are sleeping. The release of stress hormones like cortisol and norepinephrine triggers activity in the brain that stirs you out of sleep and makes you fully alert.
But if the light is on at night, or you’re looking at your phone in the evening, this will cause the release of similar stress hormones right when you’re meant to be relaxing. That means you’ll continue to feel alert and won’t give your brain time to recover.
And what doesn’t help is the way that everything on the web and on TV is designed to grab our attention and pull us this way and that – this has been shown to cause effects similar to ADHD in the long term and make it harder for us to concentrate on any one thing for very long.
How Physiological Changes Trigger Stress
The above is an example of how stress is entirely a result of what’s going on in your life or even of what you’re thinking. Instead, stress can be a result of outside factors that physically influence you.
A way to think of it is like this:
Physical Sensations > Feelings > Emotions > Thoughts > Behaviors
That is to say that your emotions are very often the result of physical things affecting your physiology.