My week old baby hasn't pooped in 4 days, he is breastfeeding and is jaundice, but his levels weren't high enough to go under light, should i be worr?

Normal for breast: No, because breast fed babies can have a stool with each feeding, go once a or day or can go as long as a week without stooling.

Normal i some: Your typical breast fed baby can have a little poo smear every feeding or one giant blowout every 7-10 days. If soft, i don't consider it constipation. As long as baby wets every 6 hours or more i would consider things within the range of normal.

M.D. visit: If you notice jaundice at day 7 of life, this may be related to breast feeding or retained meconium. Your pediatrician should follow up to determine whether lab testing is needed.