I know exactly what you are talking about with the jumbled but incredibly vivid head space activity trying to sleep the first few days. I think after my last relapse, I finally got about 4 hours of sleep on night 3. Not good sleep... But still sleep.
Hang in there. You can get through this. Think of anything you can do in this state as an accomplishment and give yourself credit. Withdrawing can be one of the toughest things a human can do.