BF supply...

So I returned to work in May. I was only able to pump once at work, my supply def dropped. Now that I am off again for the summer I was really hoping to build up my supply again for the next 2 months. My personal goal was to BF until my son was 6 months.  I understand this supply and demand deal. I try to pump in between feedings (getting close to nothing) I drink mothers milk tea I just haven't seen any results yet! Is it over?