It is born from a feeling of insecurity. It can also arise from experiencing many changes in a period of time with uncertainty about what is going to happen. Or it is constitutional, there are people who worry excessively about trivial things as a trait of their personality.

Worry produces Qi stagnation, usually in the Spleen or Lungs and eventually weakens them.

The mind thinks a lot trying to anticipate situations or find solutions. This excessive rumination, constant thinking damages the Spleen (Yi, intellect) producing Spleen-Qi deficiency: little appetite, tiredness, loss of concentration. Rumination may occur, which is when one excessively reflects on a topic without finding a solution or being able to stop doing so. Obsession. The mind travels to the past continuously, nostalgia. There are people who think more about life than they live it.

When we are worried our breathing becomes shallow and we tense up: Lung-Qi deficiency.

Worry and excessive rumination consume Heart-Blood: we can have insomnia, anxiety, palpitations.