my 7 month old ds has never slept well. had much teething pain, has one tooth now. He has always woken frequently ,used to be settled easily. Last few weeks waking up crying like colic pain, after a while passing wind through nappy. doesn't have this problem during day just at night . can be awake for 1 hour at a time. he may drop off up to ten times then wake up screaming when still in my arms before eventually settling again. what foods or anything could be causing this.