Hi Jan thanks for the reply. My father's mother (my grandmother) has fibromyalgia. Do you know if that could of been passed down to me? Thanks again.

Type of Myotonia: .

Country: uk

Sarah, fibromyalgia does seem to run in families. It is much more common in females.

This is a good information page about fibromyalgia:
Fibromyalgia Q&A

There is a condition called Ehlers-Danlos Syndrome which is hereditary and the hypermobility type is strongly associated with fibromyalgia. Many people with this condition are "double-jointed" or very flexible because of a defect in collagen synthesis. This page shows one of the criteria for diagnosis:
Beighton Score

If any of that seems to fit, I would suggest seeing a rheumatologist.

Jan

Type of Myotonia: Thomsen's

Country: US