That's one way to look at it, kindness is not selfish in my opinion because yes you may get a good feeling helping someone and people may think that is selfish, but is the amount of time you spend on kind acts worth the feeling? There are many things you can do which don't involve kindness but make you feel good, that I believe is more selfish than being kind.

But of course this is not the same for all situations, for example liking photos on Facebook will give you absolutely 0 dopamine fix unless you really enjoy pressing a button, it is merely an unconscious action we do. Actual kind acts like helping an old person with something, offering someone to share something of yours, just listening to someone who needs it are satisfying.