Believe it or not, and many people don't, there is reflux you can't see, appropriately named "silent reflux." Josie's was the opposite so easy to see, but her inability to fall asleep while horizontal would have been our first clue that she had reflux at one month of age, rather than her having to wait till 3.5 MONTHS to get treatment.
A lot of quality Mommy-baby time was lost there.
So that's why reflux was my first thought. There's a Reflux 101 post in the Reflux FAQ's board with some things to look for and some things you can try; even if you don't suspect reflux, can't hurt to try keeping baby upright for 20-30 minutes after a feed, or putting to sleep on an incline. Many reflux babies - many babies in general - often turn out to prefer sleeping on their tummies, but that's a matter of preference for each family to decide, with a doctor if need be. Generally, once babies can lift their own heads it's considered to be low-risk, although Nat slept on her tummy from Day One despite being a floppy bundle of baby.
(She got strong enough fast enough, tho!)
One things I've been known to resort to just to get things re-set is to either wear the baby (sling, baby bjorn) to get her to nap, put her in the stroller and go for a walk (gets ME out of the house and out of the nursery!), or just go driving and let baby sleep in the car seat. Seriously. For one day, just to get baby's sleep caught up and to get Mom some fresh air!
Sometimes once baby isn't OT any more, naps go more easily since they aren't OT and jumpy/jittery. For a while, before Josie's reflux was diagnosed and treated, her EASY looked more like A=1 hour, S=45 minutes, repeat till bedtime, squeeze in E wherever it's closest to the "right" time.
This resulted in maybe 4-6 of those short naps per day, and for at least one of them I'd sometimes let her sleep on HER tummy on MY tummy (go pee first, don't ask me how I know this
) and we could often get up to THREE HOURS of quality restorative sleep this way, but usually 90 minutes - an ACTUAL NAP!
Anyway, once we got sorted, THEN we could start fresh.
Oh, with my more Spirited one, Pat/Shush DI NOT EVER work!! I tried for THREE DAYS RUNNING (had DH take the older one to visit the IL's for a weekend so had time alone and to spare) and got NOWHERE!!! It just got her more wound up and I had to give up and wear her or my older DD would have gotten zero Mommy time.
It just doesn't work for every baby.
Somewhere around that age, one full sleep cycle is about EXACTLY 45 minutes; I could hacve baked bread by Josie's naps, although instead I found I could mow the entire lawn in that time.
If baby's napping for 30 minutes or 60 minutes, that suggests (to me, anyway) an incomplete sleep cycle and therefore possibly not fully rested.