Overnight nappy was dry?

Amber • 20 years old, mumma to my beautiful boy Oliver and expecting my second in Jan 2018 👶🏼
I changed bubs nappy before we went to bed at 1am and then I woke up just before at 8am and fed him , then changed his nappy and it was dry? He seems fine , no temp, fed like normal, no fussing, should I be worried? I'm waiting till his next feed to make sure he wets his new nappy but I'm just confused as to why he didn't go overnight