K.
Isn't it funny how babies sleeping through is such a blessing and a curse at the same time? My daughter slept through at 11 weeks. She did it 2 nights in a row and then didn't repeat until she was 6 months old. A few lessons to be learned here...
1. Just because your baby sleeps through now, doesn't mean that she will next week.
2. If she does it for 3-4 nights in a row, your body will adjust and you will not wake up so engorged again.
I will admit that there have been a couple nights where I've actually woken up my daughter around 4 AM by sticking my breast into her mouth to get some relief. But if you just stick to nursing and never even look at that pump, everything will work out just fine. This is kid #2 for me - I nursed my son for 20 months and my daughter's 7 months now. It always amazes me how well equipped our bodies are to feed our babies. All we have to do is feed them when they're hungry! Hang in there and good luck with your baby!