I've been combing through the old boards looking for answers, but love to hear from you if you had a not-unicorn newborn.

My (large, 12-pound) 5-week old baby boy is sleeping in 1-2.5 hour blocks of time, around the clock--mostly it's closer to 1-1.5 hours, his longest stretch is consistently after midnight. So, I'm sleeping anywhere from 45-90 minutes at a time, at most, since he was born, and I'm a zombie. I hear people talking about naps and nighttime sleep being 2-4 hours at least around this age, which sounds impossibly wonderful.

Here's what I'm doing so far:
_nursing every 2 hours minimum (we used to do more frequently, ped said he was snacking too much and less frequent/bigger meals=longer sleeping)
_trying not to let him stay awake longer than 90 minutes
_nurse (he takes 4 oz~), swaddle in a summer infant swaddleme, walk slowly holding him upright to burp for 5 minutes, put him down while very drowsy in a Rock N Play next to our bed, dohm white noise right by his head.
I don't usually have a problem getting him to go down, he just doesn't stay asleep very long. We've also tried putting him in his crib, in our bed to co-sleep, on the couch cushion next to us, and in his giant snugapuppy mechanical swing, none of which work.

If you were in a similar situation, will you share how you got your newborn to sleep for longer stretches? I see that many of you implemented a "bedtime" routine--love to hear about it or anything else, technique, timing, product, etc, that worked for you