I haven't had a decent sleep for months and I am exhausted. I used to be able to go to sleep at 10 and sleep til 2 or 3, then very intermittently until about 6, which wasn't great, but lately it's declined further and I am awake just after midnight with very little sleep post then. It's not because I am not active - I work, and come Friday I will have done 21 shifts in 24 days. I'm dead on my feet. Even after a 10 hour shift a few days ago I couldn't sleep past midnight. What can I do? I'm starting to worry about it.