Where is the Milk?

This is mildly depressing. I'm getting less and less milk as each day goes by, while pumping for longer and longer.
Why am I doing this anyway? This feeling is compounded by guilt at whiling away 1 hour of office time on pumping, while also using my lunch time to do this. that's 2 hrs of good time being used to get much too little milk!
and I can't and don't want to leave work late because I have a baby I want to get back to to feed.
so
life is reduced to a cycle of feeding, desire to feed, longing to feed, necessity to feed and pumping to feed later
and the pumping ain't going too well
not in a good mood here, as one can tell