Jaundice

I know 60% of newborn babies in there first two weeks of life have jaundice but it goes away. My daughter whose 6days old now had a little bit of signs of it (yellow skin color on face and white part of the eyes) when leaving the hospital and at her doctors appointment. Her doctor said of the hospital wasn't worried about it then he wasn't but he said it's also on her chest now and that if it spreads to her hands and legs to call him and we'd get blood test done Monday. Well that was Thursday and it's Saturday and her legs are now looking a bit yellow. The doctors office is close and I don't think he'd remember that Monday is 4th of July so the office will be close then too. Is jaundice a serious thing? Do I need to take her to the emergency room?