I have been back at work for a couple of weeks now. I only work m-f 8-3:30. I am pumping at 9:20 and 12:20 for about 15 minutes. I have noticed that I get way more in the morning than I do in the afternoon pumping session. The morning is anywhere from 6-9 oz from both breasts but the afternoon is only around 4 maybe 5 oz. Is there a reason these are so different? my daughter is 4 months.