Kiln dried pine is safe for rodents. I know many breeders who have always used pine. I keep both mice and rats on it without any issues. I've seen no difference in the health of the rodents since I switched from aspen to pine.

It's fairly normal for mice to act agitated when you put them in a new environment. They calm down eventually. I use 20QT tubs as a maternity bin for 1-2 does, then move them to a 10 GAL when the pups start leaving the nest.