Oh,I have learned a lot, I would not say from programming but from the career as a whole

Never get peer pressured
Always show empathy
If in a leading position, taking care of people is your top priority
Overconfidence will destroy a lot of good work
People by definition will always remember your mistakes
Never get over involved in the company you are working for, it's just a job
Your health is more than important
Nobody knows everything
Always be humble
There is a lot of bullshitters out there
Success is relative
Competition is high and there is always someone with better skill set, so you will suffer if you don't accept that