My lo is 3 mths old today.. Recently these few days I notice that his eyes is kind of weird.. Both his eyes will move from side to side in a very very fast speed.. Is this normal?

Hi, i would think it's better to consult a pediatrician. I've got a friend's baby had the same issue. The doctor referred them to a eye specialist and it was diagnosed as Congenital nystagmus. Nystagmus most commonly causes the eyes to look involuntarily from side to side in a rapid, swinging motion rather than staying fixed on an object or person. It usually develops in infancy, usually between six weeks to 3months.

Do his eyes kinda jiggle in a jerky movement or is he just looking around from left to right rapidly? If it is the former case, it could be Nystagmus (dancing eyes) - its not considered a serious condition, and accordingly mostly would go away after a while, but you should consult PD to be safe. https://en.wikipedia.org/wiki/Nystagmus

Does any of your family have Nystagmus? it's usually passed thru genetics. Can your LO hold his eyes center and focus if he has something to look at, or do they always wander?