Naw, I can relate. You are not a wimp. The first few times I let mine free-range, I was a nervous wreck. I stood over them and followed them around to make sure they were safe and wouldn't get lost. Ha.....
I too did it slowly....as I look back it was more for me, but that's the way it was. Get into the habit of calling them back into the pen after they have been out for a little while, give them their favorite treats and they will very quickly come to your call.
This is particularily handy when you want them in from free range, for whatever reason. I let my girls free range when I am home and they come running now when I call them so they are very easy to put into their pen if I have to go somewhere. Course they always get treats.
My girls love to be out and about, they have a routine and depending on the time of day, I can tell you exactly where they are. Although I have over 6 acres, they do not wander out of sight from their coop/pen, 1/2 acre at best. I have placed some small shelters (dog houses actually) around the field so my girls can duck out of the way from hawks and they sit in these little shelters when it rains. I love watching them from the house.
Anne