I woke up this morning and noticed my sons diaper wasn't as full as usual for when he first wakes…

I woke up this morning and noticed my sons diaper wasn't as full as usual for when he first wakes up, about an 30 mins to an hour after I went to change him again because he pooped I still notice he hasn't peed. He ate breakfast and drank his juice and drank a bottle through the night? Should I be concerned?