Thank you for the detail,
One possible cause of your symptoms is something called "restless legs syndrome". While it is more common in people older than you, it can occur in younger adults as well.
The classic symptoms include a difficult to describe sensation in the legs, discomfort, creeping or a feeling that the legs need to be moved. It occurs at rest and is relieved when walking around--therefore it causes difficulty with sleep.
It can be associated with underlying illnessess including iron deficiency anemia, which is more common with colitis.
It does not sound like a circulation problem. This type of issue gets worse when walking and better at rest.
Thyroid problems can cause cold extremities--I would recommend having your level checked as well.
The treatment for restless legs, if this is your diagnosis, includes medications such as Requip or Mirapex, stretches before bed, avoiding caffeine, tylenol or motrin and warm baths before bed.
Here is more information for you about restless legs..http://www.mayoclinic.com/health/restless-legs-syndrome/DS00191
Feel free to ask any follow up questions you may have,
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