Re: One side hurts, the other is OK...
It could be that you have a shorter or flatter nipple on the right than on the left, or more engorgement on the right. Both would be preventing optimal latching. You might also have a faster letdown on that side, which could cause baby to use a more painful latch in order to control the flow.
Coolest thing my big girl said recently: "How can you tell the world is moving when you are standing on it?"
Coolest thing my little girl sang recently: "I love dat one-two pupples!"