Candace,
I also have experienced a lot of clogged ducts since I started nursing. I have found not using an underwire bra to really help. My clogs have been the result of "milk blisters" on the nipple and I had to break them up to get rid of the clog. I had one that lasted for 4 days and really affected my supply. Just keep pumping through it. I also felt like my supply was at a standstill around 1 1/2 - 2 ounces a session. But I think that was all my baby needed at that time. When she started demanding more, my supply did increase. It takes a lot of trust. Remember in the beginning the baby won't need much milk. Probably only 1- 1 1/2 ounces every 2 hours for the first week or so. Your supply should increase when your baby arrives and you still have plenty of time to increase before she gets here. The thing that helped me a lot was having a baby scale to measure intake. It helped to put my mind at ease that she is getting enough. Good luck.
Jennifer