almost 3yr old terror

my almost three has turned into a little monster.. here's a little background. since birth he was always alert, never closed his eyes while nursing was always looking at what was going on. then about 7mth he started to scream all the time - this went on till he was 2 when i found out he was wheat and dairy intollerant. he gets ezcema, asthma and extremely bloated ( i mean like pregnant man). we stopped the dairy and wheat completely - unless he snacks on something that isn't his - but for the most part no dairy or wheat. oh, he also can't eat watermelon, gets terribly bloated and almost bleeds when he does a poo.

so he started kinder end of jan and he has started this screaming again - terrible shreaking screaming that is absolutely unbearable.. it literally makes me want to rip his voice box out (ok, ok, i wont.. but..) as far as i can see he is not eating any foods he shouldn't be.. and he does understand that words is the best way.. once he is calm he always apologizes for his screaming and said next time i will use words...etc.

ok, so i need help. anyone encountered this kind of screaming. i live in melbourne so if you live nearby you can probably hear him.

WHAT SHOULD I DO???
(i even had a neighbour who threatened to call child services when he was almost a year as she said i was torturing him.. we moved in the end.. but he literally sounds like someone is murdering him)

please any advice.. i was thinking maybe there are other food allergies i should have him tested for.. which could be setting him off??
thanks in advance

I am not a doctor, nor do i have any medical training, but . . . . .
have you had him checked for things like intestinal problems or spasms in the bowel etc chron's, divaticilitis(sp) etc
have you taken him to a paed???
is it possible he is sick?
In kids there are small glands around the belly button. If they are fighting something, these glands flare up- the pain is as bad as appendicitis. Perhaps he is getting bouts of this and his glands are up for a reason?
maybe there are other foods that are annoying him- maybe get allergy tested?
next time he is screaming , i would rock up to the emergency room of the RCH and ask for their help. They can at least run tests to see if there is a reason
He can't go on like this and either can you!
good luck and let us know how you go
odette