When lying on his back, he should fix his gaze on your face briefly, and will soon follow your movements with his eyes. In the next few weeks, you will find that he will become either excited or calm and quiet when he hears your voice. He may also smile back at you when you smile. This does not mean that anything is wrong with you or your baby. It is merely a reflection of changes in his sleeping patterns and activity level.
Most babies peak at about six weeks of age, and then get better.
Remember that at this age he has only one way to communicate, and that is crying. You will quickly learn to tell his hungry cry from his tired, fussy, painful, bored and other cries. Remember that your baby does not always need something when he cries. Many times your baby will cry because of hunger or discomfort. However, he may also cry because he needs to sleep.