I would try letting her out at first in the daytime, to get her used to the cold again. Do you have a shed or garage that's colder than the house, but warmer than the outdoors? Maybe you could transition her there for a few nights.
Honey, don't panic! If you think the sutures are going to cause a problem, sterilize your little embroidery scissors and cut them. Don't mess around with trying to get the ends out - just cut the middle. And remember that she's less likely to lay when stressed - it's not impossible, but less...