Homsa, another good book re: biomed, if someone hasnt already suggested it is Jacqueline McCandless' "Children with Starving Brains". get it on amazon pretty cheap. Its my bible though there are few new ones out. We follow her "protocol" and havent gone wrong yet.
Our boys improvements werent wow like, but are gradual. We look back now over the last six months or so and that is when we really see the improvements. For starters, he is beginning to learn much better from his aba sessions, limited as they are.
LOng way to go and its a "marathon, not a sprint", its expensive and its frustrating but for us, its been a godsend in terms of reduced behaviours sleep and general health particularly digestive health.
The feet thing, well I would guess that a reflexologist would tell you more abou this than me, its all connected. We had our boy at a relexologist and a cranial osteopath, both of which were very interesting in what they told us.
NHS can start you off on tests but you must ask for them, sometimes demand them. We had a whole host of blood/urine tests done, some of which were useless, but the vitamin and lead were of interest as were the amino acids. They will do a thyroid test but wont tell you about ts3 (important marker) unless there is a real problem with it, a big problem.
WE have all our tests done either at Dr Heard or through IWDL both in the UK. We discovered our boy has immense gut problems and in particular has a low resistance to measles, which is as bad as having high receptors to measles.
Anwyway, i gave you the link to "treatingautism.com" and they can help you immeasurably if you wanted to go down this road.
I of course, highly recommend it.