Yes, it looks like a growth spurt. As Erin said, feed him as often as he wants. It usually lasts anything between 48 hours and a week. If you follow his clues and nurse him your body will start produce sufficient amount of milk for his new apetite.
BTW, growth spurts occur around the timetable given in books. The first one is at 6 weeks, some report it earlier, next at 3 months, then 6 monhts and 12 months. But babies don't always read books :lol: .