On one occasion I fed my son when he was about a month old and I think he sucked so hard I had extreme pain in the back part of my breast. Almost like a pull from the milk duct. A month later it happened again.same breast but not as painful. He is gaining weight (95th percentile). He is 9 weeks. We have had a rough road with breastfeeding but have been doing exclusively and it is getting better. Dies anyone know what may be causing the sharp pain deep within when he sucks?