Help!!!

Ok ladies.. I need your help/opinions here. I just had my second child on Tuesday. With my first I didn't breastfeed.. So this is a little new to me. My nipples hurt sooooo bad that I think I would just like to pump. How often do I need to pump to make sure that she is getting enough. Also, how do I store it? How long does it last in the fridge and the freezer? How far in advance do I take it out of the freezer for it to be ready for her. I know absolutely nothing about it and would love to hear how you are succeeding with it!!! Please!!!!!