My 3 week old baby falls asleep during feedings and just won't burp. I hold him upright for up to half an hour while patting her back pretty well. He is drinking both formula and breast milk (both from the bottle). At times he will burp twice and I lay her down, he gets uncomfortable and cries a little, I pick her up and he burps again. I have to do this every 5 to 10 minutes sometimes. Often he will demand more milk when he looks uncomfortable from what seems like gas as he does pass gas after squirming and crying some. Tell me what to do. ?