my sympathies, i often experience the same.
even when i was in the construction industry and tired myself out id still be up till 3am and out the door to work at 7.
tried sleeping tablets, hypnotherapy, excessive amounts of weed hell even hot milk. :P
insomnia was the main reason i was an alcoholic from age 15-18 (young i know)
recently my father has been making me 'funny tea' as my mother calls it and even that doesn't quite do the trick.