pandora, the other moms have given great advice, I just wanted to jump in with my experience this time around. I pumped for DS1 and could always get milk no matter when I pumped, but this time I cannot pump after a feeding and get anything. As in not even one drop...if little one nurses he gets some though. The pump is not the same as your baby and there will be days that have a little lower output than others. When I am away from baby at work I have no issues pumping plenty for him. I actually had NO stash when I returned to work (last time I had about 3-5 days worth) and just pumped enough for that first day. There is plenty of milk for him each day. The beautiful thing about nursing is that if you tell your body you need more it starts to produce more. Try not to stress out too much - keep at nursing and enjoy the time that you do have before returning to work. I completely understand that resentful feeling as many moms are forced back to work way too soon after having a baby. I was supposed to return at 6 weeks, ended up being able to return at 7 weeks. Keep asking questions and before you know it you will be through the first year and sooo glad you made it
ETA: I pump as often as my LO eats during the day. So I end up pumping 3-4 times.