How is Generalised Anxiety Disorder different to normal feelings of stress and anxiety?

For me, the key thing is overwhelm. An overwhelmed anxious brain can believe the stressors are far too great to manage. Being emotionally overwhelmed means to be completely submerged by your thoughts and emotions to the point where you may withdraw and feel frozen or paralyzed. When confronted with being overwhelmed, it can be difficult to think and act rationally, and even function in a normal way. These images are ones I’ve used in therapy to help clients articulate what they’re experiencing. They symbolise how overpowering your overstimulated amygdala is responding.

Grounding, breathing and being mindful of your triggers can help.
A combination of those techniques and therapy can drill down to the root cause, dig up the weeds and help you to replant or reframe your process.