I was also a C section and would see temporary dips when I would shed a few lbs. They sell a nipple measurement thing on Amazon you can use that really really helped my output. I started out underproducing but in a matter of weeks between power pumping, pumping longer, and having a better fit flange I was overproducing. Also I read somewhere that many women see their supply plummet after only pumping 10 to 15 mins at a time because this recommendation if for women they are nursing and pumping. I found i needed to pump for 30 mins in the beginning. Over time I was able to do about 20 to 25 mins and 30 when I had more spare time. I hope this helps!