He may eat more at each feeding or require more frequent nursing. After a couple of days, he will settle back into a pattern again. Babies under 3 months seem to respond more to internal rhythms, such as those of hunger and fatigue. Older infants are influenced more by events in the environment. By this I mean that his own organization of wakefulness and sleep, alertness, and irritability has some built-in determinants, such as his neurological maturation, that remain constant whether he is in the middle of a growth spurt or recovering from a cold.
Some babies are short sleepers from the start and some sleep more than average for their age.
They wake, eat, and sleep in a totally random pattern. If yours is a very regular baby, he will more easily fall into a schedule. By 2 months, some babies can sleep five to six hours at a stretch. Your goal is to make sure they're nighttime hours. If he's very irregular, you may have to take the initiative and make some parts of his life as predictable as possible.