Hi Becky!
My daughter is 3 months old now and has been sleeping through the night (mostly) since she was two months old. I let her sleep. She goes in around 10pm and wakes up around 9am. I breastfeed as well and I woke up and pumped a few mornings because it was painful. I would try to last a lillte longer each day before pumping so my body would adjust 4am, 5am, 6am..., and my body seems to have adjusted to this routine and I rarely have to pump in the mornings.
She is growing, gaining weight, and has a lot of wet diapers. She seems happy and alert when she is awake, and seems to be developing just fine. She also naps during the day. My ped says to feed her every four hours, but since she is sleeping through the night, I feed her when she's hungry, about every 3 hours, sometimes more, sometimes less. It makes me feel like I am making up for the feedings she misses while she sleeps. I was nervous too, I thought she wasn't getting enough, but like others have said, she'll let you know!!!