There is growing evidence that sensory issues , autism and the like are caused by a parasatized central nervous system and/or GI tract.
My father has many of the same issues you describe, can't stand a crowd, noise sensitive, gets agitated in crowds or in noise. He wasn't always like this. He used to be the life of the party! He is like this now, because he developed Alsheimers. Many doctors are saying now that Als and MANY other chronic illnesses are caused by Borellia B., Bartonella, Erlichia, and Babesia. L-form bacterias that are hard to find in the body. They can be transmitted through insects and also humans secretions, even in utero. They particularly like the central nervous system.
Indeed, my daughter was born with thrush and has autism like issues. I have been dosing her with herbal antibacterials for about 4 months. (Samento and cumanda) and have seen a change in her voice which has always been abnormal. It was deep and gruff like an old drunkard, now it is more light and feminine like it should be. Her anger and tantrum issues have resided a lot. She didn't like to be held, and she couldn't pay attention when reading to her. These symptoms are gone. Her constant IBS and diahrrea is gone.
As the child grows the immune system can get stonger,Parasites can die off, others can take their place, etc. Hense the fact that children will grow out of some problems, and maybe grow into different ones later. Nutrition is a whole nother topic, but goes along with toxic load. I've read that certain parasites can cause depletion of vitamins that are crucial for the central nervous system. Vit B is one of them. You should consider giving him supplements, liquid b complex under the tounge, 2-3 times a day.(walmart has them.) Another one for the CNS is magnesium. Fulvic acid is a good supplement, it gives 60 trace minerals in an ionic base that can be readily absorbed through the cell wall. Our soils are depleted of many of these minerals, yet they are required for normal function and health. Some of them have definite antibacterial property , like boron, silver, sulpher, and bismuth, Just to name the few I have researched! there are probably more. Look up fulvics online.
Internal wormlike parasites, blastocysts, and protozoa can cause all kinds of disease states and symptoms as well. Below Iv'e attached a partial list ( I noticed many of the L-form bacterias are not on here.) Of interest is the fact that Blastocystis is an organism that takes up residience in the GI tract and affects and represses the serotonin levels!(serotonin is the substance that affects our mood, anxiety levels, sleep patterns, anger and agression, appetite, pain, and metabolism.)Since 90% of our serotonin is in the GI tract, this looks to be a very possible reason for high anxiety and moodiness. Modern medical doctors don't even think along this path, (I doubt they've even been taught much about parasites in Med school) and are quick to put kids on MAIO's (antidepressants) to cover up symptoms. Blastocystosis is more prevalent in California than in any other state. Metronidazole is the prescription med but I believe Samento may work on it as well.
http://en.wikipedia.org/Wiki/List_of_parasites_(human)
http://en.wikipedia.org/wiki/serotonin
Dr Mark Hyman and Treveor Marshall both claim that disease symptoms are not normal, weather in youth or in disease states coming upon us in aging. They all have a cause.
You can look up Dr Hymen online. Here is Trevor Marshalls link. Take the time to really look at it:
http://www.marshallprotocol.com/formum32/1263.html
and more facsinating medical info :
http://www.springboard4health.com/notebook/health_lyme_di...
http://www.bionatus.com/nutramedix/pages/cumanda_what.htm