In case you never considered it before there is a heavy PROFIT INCENTIVE for your psychiatrist to diagnose you with some form of mental illness that he is familiar with. You need to become a domain expert yourself in order to figure out if you're being manipulated for profit or if the diagnosis is legitimate.
Fair enough, although I suspect it was the act of taking time to reflect on his own inner processes which helped him and this could have occurred outside of the context of a "diagnosis" and without drugs. It's sad that in modern society people are trained to not talk to each other about their emotions and feelings outside of the context of a "sick ward" where one party is being financially motivated to behave in a certain way.
Most of them, but they don't consciously realize what they're doing in most cases. The norms for their profession slowly creep towards over-pathologizing because of the profit incentive and also because of the effectiveness of advertising campaigns by drug companies. Social norms have changed across a broad demographic to accommodate the large scale systemic misdiagnosis problem. Just because the manipulation for profit is widespread and well accepted does not mean it's not happening.
I was only giving my personal opinion based on the data I've seen. All I'm really advocating here is that every person should educate themselves before accepting any diagnosis. Do your own research and form your own opinions.