High B12 levels in 4 year old, Should i be worried?

[Jjc23]

My 4 year old has recently felt more tired than usual. He appears pale, under eyes are a little dark, irritable and his appetite has decreased. This lasted around 4-5 days.
He is slowly getting back to his normal self. Energy levels are getting back to normal and appetite is better. Still seems slightly pale with dark under eyes and irritable.
He has had some blood tests done. Most results look normal, however his B12 levels have come back as >128*, which is above range. He does not take multivitamins and has never taken supplements.

Should i be worried?

There have been a few threads before - I don't think any reported a high B12 along with any nasty diagnosis, and from conversations with professionals it is not associated with a disease state in children.