I had a fussy one, he had a lot of digestive problems. He nursed frequently I think mainly because he could only easily digest small amounts at a time, and he spit up a lot. Try giving her some simethicone (gas) drops. The box says to just give a little tiny amount, but it isn't absorbed by the body so you can actually give a whole dropper full. It helps a lot. As well as lying her on her back and pushing her knees to her chest. Ultimately, although I hate pacifiers, I had to give him one because the sucking gave him so much relief. He only like the Nuk brand, you may have to try a couple of different ones to find a shape she will like. And watch your diet. Things high in fiber, caffeine, spicy food, and diary products can all transfer into the breast milk and are hard for baby to digest.
My nipples always hurt a lot when I have to pump, I would only pump when you ABSOLUTELY have to! I pumped frequently right before I went back to work to build up a stash and then once a night at work, when LO would have been nursing before bed. Now that he's almost a year he just drinks almond milk before bed when I'm working and i quit pumping altogether, I hated it!