However, there is no harm in learning psychology, and it can help others solve psychological problems in the future; If you don't take any diploma, you can go to the library to read books on psychology. Like Zhang Defen's psychology elective course; Bi Shumin (a famous psychologist in China, often invited by famous universities at home and abroad to give lectures on psychology) books are very suitable for reading. Her books are deep and not boring at all, and I like her books myself.
Maslow, a famous American humanistic psychologist, wrote a book "Help You Know Yourself in an All-round Way" to dissect your own psychology.
The famous psychologist Freud's "ego and id" is a book about knowing yourself.
Marx also recorded a lot about psychology and self in Humanism.
I am now studying psychology by myself. I hope my answer can help you!