4 Year Old Lost Color In Face - Reason?

My 4 year old nephew was fine all night and then we sat down to eat pasta and he started acting weird. He first complained about his finger that it hurt but there was nothing there. He actually started to whimper about it and looked like he might cry. Then he started yawning and said there was something wrong with his breath. He got really lethargic and tired and kept yawning and when we said what’s wrong, he said “I dunno there’s something wrong with my breath.” He wasn’t choking. We all noticed he turned totally grey and his lips were white. My mother pulled him out of the high chair and he said he wanted to go to bed (NOT LIKE HIM).

We thought he was having an allergic reaction but nothing happened after that and in fact he got his energy back and acted pretty normal. We made him chicken and noodles and he ate ALL of it.

I looked on-line what this could be and didn’t really have luck.

Anyone have any idea of what the hell happened?