I have a 4day old newborn. she's been eatin well, but she has been asleep for about 7hrs now since last fed early this morin. shud i wake her to feed?

Yes: Yes, you should wake her and feed her. At this young age a baby should be fed every 1.5 -3 hours depending on whether you are breast or bottle feeding.

Newborn sleeping: Yes, newborn babies should not sleep for more than 4 hours, At that age they should be feeding every 2-3 hours 4 max. If you get to 4 hours wake the baby up. If the baby is not feeding well and falls back to sleep the baby needs to be seen by the pediatrician asap.