I have a 3 week old girl and would like to build a supply of milk in the freezer so my husband can feed her. My daughter is feeding every 2.5 to 3 hours for 25 to 40 minutes each time. How can I build up a supply in the freezer? Should I pump after each feeding? If I do that will I have milk for the next feeding? Should I feed her formula once a day so I can pump once a day?