Define 'sleep normally' - not able to get to sleep, not getting restful sleep, waking up at odd times, etc.?
Apart from the normal suggestion to follow good sleep hygiene - normal things like lavender massage, relaxation methods, breathing techniques, hot baths and warm milk - chill before bed and keep bed for sleeping only, it'll help you get better sleep.
It's often down to anxiety and issues in life - deal with whatever you can deal with the best you can, for general worries or anxiety it might be an idea to try Emotional Freedom Techniques...I don't buy into the whole energy field stuff, I think it is more mental, but my mother learned this via her hypnotist and it helps her a lot with sleeping problems and depression. A similar thought is this little finger trick.
Melatonin is love - apparently those of us on the spectrum are lacking in melatonin, for most people taking this is the best thing to help with occasional sleeping issues (i.e. better than herbal or over-the-counter sleeping pills), or I've had some good results with 5-Hydroxytryptophan (5-HTP) too. You can pick up these pills in many health stores. Another something to look for in health stores would be valerian root or a passionflower tincture, oh and up your magnesium, calcium and B12.
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Bloodheart
Good-looking girls break hearts, and goodhearted girls mend them.