Normal. After around 6 weeks, many exclusively breastfed babies will eventually slow down their bowel movement frequency to as little as once per week. It's not constipation. It's just that breastmilk digests so thoroughly and leaves so little waste that the baby doesn't need to poop every day. When she does go, however, expect a diaperbuster!!!
There is nothing you should do at this point to "help" your baby except to continue to nurse on demand, take away any solids if you have been offering them (it's too early for them), and maybe put your baby in a warm bath if she seems uncomfortable. The warm water often stimulates a baby to poop. Of course, then you have to go and scrub the tub...!
Coolest thing my big girl said recently: "How can you tell the world is moving when you are standing on it?"
Coolest thing my little girl sang recently: "I love dat one-two pupples!"