Exclusively Pumping

I'm exclusively pumping because I have to go back to work soon and my baby has trouble sucking hard enough to get anything when I tried to breast feed. I'm 15 days o.o this morning I got 7 oz pumping and every time I've pumped its been less. Next was 5 oz. Now I'm down to hardly 1 oz. Anyone have any ideas why this is happening? Could my milk production be drying up already??? Hope this is the right place for this question.