Poop Problems

LO has been ebf and absolutely refuses a bottle (I've tried many different kinds) and sippy cups so I can't get her to drink any juice. In the last two weeks she has had really hard poops, like a solid ping pong ball and she screams so I know it hurts. I've tried so many things, she even ate an entire thing of prunes at dinner last night and we some up to another rock in her diaper this morning. What can I do???