In this same job, I've switched between so many shift patterns to a few months of 9-5 so often, but I've done my best not to break my body clock. I tend to eat at regular times of the day and just strecth the sleep part.
It's just like a week of late nights (7am to bed).
But, great news. I have landed a new job and this week 'should' be the last night shift I ever do (If I have my way...)