3 week old sleeping/feeding schedule, normal?

Baby was born 3 weeks ago, he feeds every 4 hours and it varies between 3oz and 5oz, the later it is he eats more, he usually has 5oz at 10pm and could sleep up to 6 hours straight, I don't wake him for feeds because I was told he doesn't need to be, he is way above birth weight. So up until 2 days ago he would only wake for feeds, then stay awake for maybe 15-30minutes then fall back to sleep, now he can stay awake for much longer, right now it's been almost 4 hours since he woke for a feed and his still awake, ready for his next one. Earlier he stayed awake for 2 hours, and it was the same yesterday, still sleeping well on the night though. He doesn't cry at all either, his not fussy, he seems soo calm like all of the time.

Does the feeding and sleeping sound okay for a 3 week old? He was born at 39 weeks