Not knowing more details no one can be of much help. Smoker , Modifications , experiance,
What you were trying to smoke, These are questions you need to answer for us to know what to help you with.
There's ALOT more to smoking (overnight or not) than light it, put the meat on and take a nap.
The folks that do overnights in bed have many hours logged on their smokers and they usually have a UDS or an MES smoker along w\ the proper thermos to wake them if temps get to high or low.
Give us the details and we can make some suggestions.