3-4 week old schedule?

 I am a first time mommy and my three week old has already flipped his days/nights and is doing pretty good however, during the day he barely naps. He will maybe take two 30 minute naps and that's usually on me and at night goes about 3 hours in between feedings (EBF) with no awake time Inbetween. So I am not really complaining because I know that it's pretty awesome he sleeps so well at night but I am just concerned that he isn't sleeping enough during the day. Should I be encouraging him to nap more (like put him in his crib in his dark room-usually during the day the windows are open and it's super bright) or put him on some sort of schedule? The reason I ask is because it seems by 7pm he is exhausted and sometimes is super cranky throughout the day.