Thank you, Ricobord... I believe you've answered my query.
What you describe is called Dysesthesia. Here's the wikipedia page.
http://en.wikipedia.org/wiki/Dysesthesia
The trickling water feeling is usually associated with Fibromyalgia and nervous system issues. It is definitely worth a trip to your doctor to get your nervous system checked out.
Have you ever considered Fibromyalgia? When I first started getting sick, that was one of the first symptoms. I had it in my head and legs. It was mostly dismissed by everyone.