5 day old hasn't pooped in 2.5 days...elevated bilirubin. Help!

She had elevated bilirubin in the hospital that they were keeping an eye on, but sent me home because it didn't reach the levels where treatment was necessary. They told me to breastfeed every 2 hours to get things moving since a big poo would help expell the excess bilirubin, but nothing has happened since she's been home! She's rooting, tooting and acting like a normal newborn and looks to be less jaundiced to me. I'm just worried because I have to bring her back to the hospital this morning for repeat bili levels and I think they'll be high because she can't poo. Anyone gone through a similar situation?