NButt, I too had problems with daytime naps. For her first 19 months I breastfed her to sleep for naps or slung her (had to walk outside though, at a steady pace!), except for the days when I worked (from when she was about 15 months old) and my husband used to sling her.
But from then on I didn't have that tool so I slung her for naps in a Boba carrier. I really recommend slings and I've never ever used a pram and don't aim to get one for my next.
A tired child in a good wrap should go to sleep easily. I say 'easily' as sometimes nothing worked. I spent the first 2 years of her life trying to get the stars in the right alignment to get her to sleep.
Now, many people will recommend The No Cry Sleep Solution. I had it and have read it, as has my husband. It's a lovely book and helps to make you feel less like a fool for what other people regard as 'pandering' to your insomniac child. But I and others didn't find it worked as a quick fix. I think in some cases it reassures you, keeps you going while you ride the worst phases out. Nevertheless, there is good stuff in there about sleep associations. Looking back of course that was what the issue was.
Have hope. My child went from our bed to her toddler bed at 22 months and I refused to feed her to sleep but stayed and cuddled her to sleep (and she cried on and off for an hour on the first nights, but it was angry crying, not desolate 'abandoned' crying) and she slept through. She sleeps through 10 out of 12 nights. Compared to waking 8 times a night, this is a miracle.
She's still slung for daytime naps (although I'm now pregnant so that's going to probably end)
Sorry you had a tough few days. Heartrending, isn't it. And please don't, like me, think you're doing anything wrong. This is so common, and largely down to your child's personality. Try to drown out all the friends and family who seem to disapprove or who ram their 12-hour sleepers down your throat.