my 3.5 month old baby has stopped conversations wit us from last 3 days. stopped cooing also.. in between sometimes makes some sounds. looks at us n smiles bt no conversations. he had taken vaccine frm there onwards he has become very cranky and cries during sleeping time and feeding time. has also reduced taking feed intake. sticks his younger out n makes bubbles makes eye contact n smiles bt soon looks on other side. he also has some loose motions from past 2 days is this normal? I'm worried cz he has stopped cooing and conversing wit us like earlier pls reply