My newborn slept for four hours straight last night. i woke her up to feed . is this normal ?

Yes: it is not uncommon for a newborn to sleep more specially if it was a difficult labor, or you are on some pain medications It is important to to wake baby and feed every 3 hrs because baby can become hypoglycemic and more sleepy!

Yes: Sleep intervals are driven initially by feeding schedules and need for restorative sleep. Babies who need a feed will generally wake for it. As they pass 8 or so pounds they can sleep longer between feeds and those approaching 10 lb may go all night without.As long as they are thriving and feeding well during the day, you rarely need to wake them.Premi's/those under 8 lb would be the exception.