Are you doing anything differently that has disrupted your sleep schedule? There are a number of things you can do to address this, this has happened to me due to stress and bouts of anxiety and even minor adjustments make a big difference.
- exercise early in the day. If I exercise after 5pm my muscles are all twitchy at night.
- no caffeine after noon.
- no smart phones or tablets an hour before bed - this is HUGE! the blue light from the screen really really interferes with sleep by supressing melatonin
http://lighting.com/light-smartphones-delay-sleep/
- meditation apps - I know just said no smartphones but there are countless apps for helping to relax and prep your body for sleep, you use earphones and the screen is black so it's fine. This has been very helpful when i feel severe bouts of insomnia.
- exposure to morning light - get out there at 8 am, no sunglasses! Absorb as much of the sun's light in the morning. This will help reset your circadian rhythm.
It's amazing what power light has on our sleep patterns. It controls our sleep patterns. I also agree with other posters who have suggested a bedtime routine.