Hugs to you xxx I was wondering if he has any other symptoms, diahhreah (sp), loose, explosive or watery? Any mucus in the poo? Blood?
He is at the prime age for colic and wind, have you tried any wind remedies to see if they work? Also warm baths, massage of the tummy gently which you are already doing, and bicycling the legs can all help. I used gripe water and infacol which is available under different names in different places, the active ingredient is smithecone. As I said, I would expect colic unless you are seeing any other symptoms as detailed in the first paragraph.
With an LI intolerant DD it always pays to be careful, so trust your instinct and visit your doctor if you are concerned xxx