Hi My Son Has Severe Autism And A Very High

hi my son has severe autism and a very high pain threshold, along with the autism he has food intolerances and bowel problems, he is not very verbal and can not communicate with anyone
the problem started last Friday where he had 6 or 7 large bowel movements rangeing on the Bristol stool chart between a 4 and a 6, then Saturday night during his sleep he vomited and had a bowel movement number 7, sunday morning he had about 8 bowel movements of a number 7and did not want to eat and seemed very tired and lethargic, Monday and Tuesday morning he had another bowel motion number 7, but seemed his normal bubbly self and was eating and drinking fine, today he has gone back to being tired and lethargic, not wanting to eat and has had 3 bowel movements of a number 7, at first I thought it could have been a bug he has picked up, but no one else has got this so now I am wondering whether he is constipated and the number 7 bowel motions are overfull instead of diarrhoea, he is on medication to help control his motions, but I am unsure whether to give or whether it is just a bug as he normally over his constipation problems quickly and this time is going on a lot longer