Awww hun periods of bad sleep SUCK!
I'm not sleeping well atm, but I'm putting it down to the fact we're in the spare room whilst we decorate ours (I never sleep well when things are different).
At the start of the plan I was exhausted but it was only for a couple of weeks. I soon settled down. If anything I sleep more now than I used to!
How long have you been on plan for? Have a look at your diary and check you're not cutting too much out of diet as this will make you tired and will affect your body.
Also, even though you don't feel stressed, are you? Is work/money/life in general causing you stresses at the mo?
When I have bad bouts of sleep I always try to get some RnR - have a nice bubble bath, hot drink before bed and if money allow, a facial or something at the local beauty place.
Hope things work out xxx