My nerve block lasted 6 hours. My arm, much like my penis, was a complete wet noodle for those 6 hours. Couldn't feel a thing. Most of the pain was up in and around my traps. Like I said, there was slight discomfort to my body, in general, due to the sling, but all of this sounds really excessive.
Every doctor is different, though, and if you trust him, I guess you can't go wrong. Just sounds inconvenient to me.
Did you ask how long you have to stay in the sling? The nurse who discharged me told me 2 weeks (or until I saw my doctor for a follow up) and when my doctor called me on the 3rd day, he said I could have taken it off the day after surgery.