I'm using Medela Pump In Style. I've been trying to pump after each feeding and recently, I realised that my nipples will swell to almost double the original size (esp for my right side) when I start pumping. It also gets really painful at times. And the suction from the pump is also very weak despite turning it up to the maximum power. After pumping for 10-15 minutes or so, the milk collected from my right side is only about 1-2 oz and yet I know that my right side is still full of milk because when I tried squeezing it manually on a few occasions, milk will squirt or flow out. I'm wondering if this problem is due to the size of the breastshields I'm using. If it is indeed due to the size, does anyone know where I can get breastshields of the right size?