Hi Annie,
Did u try using the avent manual pump? This pump can help to pump out more milk compared to other brands. Alternatively, can use the electric PIS also not bad. Compared to my previous records, it gave more milk..I used to have only 30ml per expression also..now slightly better at 50 to 60ml.
RE the pain, I've also experienced this b4, try taking a super hot bath n massage that area. It will help. I once had a lump which is like a ball, din go away despite massaging n seeing the doc, I pump constantly n it finally went away.