@MeSci my tryptophan levels were normal on my tests. But I found this, it could apply to a dysfunctional vestibular balance problem. This has always been a huge/debilitating issue for me since becoming ill. My onset was an acute vertigo attack.
http://www.autism.com/symptoms_toe_walking
Toe walking is quite common in young children, age 3 and younger; but toe walking, especially in children 5 years and older, is often associated with neurological immaturity. Many parents and professionals are not aware of the various interventions used to treat toe walking. The following interventions are listed from least to most invasive.
Physical exercises are sometimes used to stretch out the tendon in order to reduce toe walking, but this treatment has had minimal success.
A dysfunctional vestibular system, a common problem in autism, may be responsible for toe walking. The vestibular system provides the brain with feedback regarding body motion and position. It may be possible to reduce or eliminate toe walking by providing the person with therapeutic vestibular stimulation (e.g., being swung on a glider swing).
Toe walking may be directly or indirectly related to a visual-vestibular problem. I have conducted several research studies with Melvin Kaplan, O.D. at the Center for Visual Management in Tarrytown, New York. While conducting these studies, I observed four individuals who were toe walkers. In each case, their toe walking was eliminated within seconds after the child began wearing prism lenses.