Hi, David.
Welcome to SR! It's a great place with lots of support and advice.
I have no experience with Norco, but once you get rid of any addiction it takes some time for your body to adjust itself to new life. Time which brain needs to recover may differ a lot for different people. Have you seen the Doc about stomach cramps?
You may check also the thread on substance abuse. I'm sure you'll find some useful info there
Substance Abuse - SoberRecovery : Alcoholism Drug Addiction Help and Information
Best wishes to you, take care and keep posting.