Maybe it is the sweet smell of animal farts. A friend on CPAP with lots of animals which sleeps in his bedrooms tells me he sucks up the animal farts all night long. Yuck. I don't know why he does it. I'd kick those animals out. LOL.

It's probably bedbugs. They say they have a sweet smell. I'd call an exterminator. Burn all your sheets, and bathe a lot.