Depends on your habits, if you work all day and run around on top of that , you will be exhausted by the evening, so no bothersome thoughts, also if you meditate or relax during the day , same thing should happen , I believe that if you spend the whole day stressed your body will need a few hours to relax and If you are not in the habit of waking up early and going through physical exertion , followed up by mental one , you will get that , you will go to bed late , watch movies that leave you half asleep, so it's a downward spiral , you get up late, miss the day and enjoy the night.
When I've had the occasional happening, I just stay in bed, after half an hour or so , I'm asleep , other than that tea and blissful music , but only if you "take it" a few hours before you want to sleep, so just take an hour to relax.
Waking up in the middle of the night is a indication of a stressful lifestyle , or a emotional or mental imbalance , that's what I think, I don't know much on the medical side , so that is that, see you around :). get the conversations going :)
My sleeplessness happens most times when I've had nothing to do all day. I might have had a nap or two during the day and then my body doesn't feel the need for another nap at night.
Eventually I'll sleep off but there's always some sort of war in my head before it finally happens.