I just wanted to say... WOW! sleeping so well at 5 weeks of age!!!!!
My little man used to wake every 2 hours every night for a feed in the early weeks. He wasn't much of a day napper either. It DOES get better! My man only wakes once a night for a feed now!
You have been very lucky to have such a great sleeper up till this point! It will pass. The slings are a great idea. DS loved his!

Good luck