the ordinary course of living affects dopamine as well

Look, I read this on Wikipedia:

The brain includes several distinct dopamine systems, one of which plays a major role in reward-motivated behavior. Every type of reward that has been studied increases the level of dopamine in the brain, and a variety of addictive drugs, including stimulants such as cocaine, amphetamine, and methamphetamine, act by amplifying the effects of dopamine. Other brain dopamine systems are involved in motor control and in controlling the release of several important hormones.
Several important diseases of the nervous system are associated with dysfunctions of the dopamine system. Parkinson's disease, a degenerative condition causing tremor and motor impairment, is caused by loss of dopamine-secreting neurons in the midbrain area called the substantia nigra. There is evidence that schizophrenia involves altered levels of dopamine activity, and the antipsychotic drugs that are frequently used to treat it have a primary effect of attenuating dopamine activity. Attention deficit hyperactivity disorder (ADHD) and restless legs syndrome (RLS) are also believed to be associated with decreased dopamine activity.

This is plentiful for me - I now realize that dopamine is a hugely complex thing and that I am out of my depth for sure (as I suspected anyway).

Ideally, the sources - articles from PubMed and not even articles on psychology today - are best to see how the studies were actually done. Every layer of distortion (a journalist reporting on a study may distort it by interpreting it incorrectly) makes it harder to see what the studies actually delivered. So, ideally, we should see PubMed links.