IUD and breastfeeding

At the advice of my doctor, I got the mirena at my 6 week post partum check up. The next day I noticed a big drop in my supply. I hardly have any extra milk, and I need to get a freezer stash before going back to work next week.

Has anyone experienced decreased supply with the IUD? I thought they were supposed to be ok. What did you do to increase supply? Im increasing water intake, power pumping, and trying to pump/nurse more often.

My baby still has enough wet diapers, but when I pump I get only 4 oz total, which is one bottle.