My DS is 3 months old and has very recently started to grunt REALLY loudly during the day and when we put him down to sleep. He's spitting up more now than ever too sometimes several hours after he's eaten. The consistency is weird...like cottage cheese (sorry if too descriptive!). He wakes up only after a couple of hours when he goes down at bedtime which is really unlike him and grunts. We did change his feed when he had a growth spurt to 'hungry baby' formula a and we haven't changed...and we changed his teats to faster flow as he's three months old. Will take him to the docs but wondered if any of you guys had experience of this?