I would suggest that if you are going to dock tails that you do it soon. We dock at 2-3 days old, just waiting to see if the lambs are strong and no immediate problems.We band them and it's easier on the lambs, and us, too, at that time. We put our lambs and ewes in a jug (special confinement pen) for a day or two to make sure they are bonding. The first time I banded tails, I came in the house and cried. It seemed tough on the lambs. However, they get feeling better in a couple of hours. The tails fall off in a couple of weeks or so.(posted 9008 days ago)If you are banding to castrate, you should wait until the testicles have descended all the way into the scrotum, which is usually 10-14 days old or so. Make sure you get both of them. I am not very knowledgeable on this subject. You might refer to "Raising Sheep the Modern Way" or some other good sheep book.
We give shots subcutaneously at a couple of different sites: in the "armpit" which is good if there's a lot of fleece on an adult...less fleece there. And sometimes on the skin of the neck, down toward the shoulder. A good livestock book will show you how to do this.
Good luck. Our lambs aren't due for another couple of weeks. We bred really late this year. It's always an exciting, kind of sleepless time!