Lambs and Lambing

I won't say I've had a lot of experience with problem births, and hence these pages are more directed toward the typical things you might want to know and might experience during your first lambing.
10 hour old Twins, Small & Spindly
From inception, birth should be expected at about 150 +/-3 days on average. You should probably have a few supplies on hand to help increase the chance of survival and boost the lamb's energy level.

You might also want to start flock records, perform some prenatal care by changing the type and quantity of feed for the ewe, and you may want to be prepared with phone numbers of a local veterinarian as well as have some information on what to do IF they're not available.
Here are some pages that might start you in the right direction:
Signs of Pregnancy Lambing Supplies Pregnant Ewes
Birthing Lambs Weaning lambs

Less than 1 hour old. Still wet.