Is it normal to have double vision sometimes?

[Tiger]

I am 15 years old. I have had eye tested before with my mummy. The people told us that my eyes are fine and I don't need to wear glasses. but I suffer from double vision while it doesn't happen all the time. When I'm sitting down like in class or like in front of my computer or sitting down on my bed, my eyes go a bit funny and it's like I can see double of something like right next to it and it happens quite a lot sometimes. If I'm watching a Youtube video sometimes, I can see 2 youtube videos talking. Or like when I'm looking at my teacher talking I can see like two heads and part of their body sort of overlapping with their normal body. If it makes sense it's really weird. is this normal?

[Everton]

I suffered that a few years ago. When I sit down suddenly or stand up quickly, I will have dizziness and double vision. Later my mum took me to saw an old doctor. the doctor told me that I had a poor health, that's why I often suffer from dizziness and double vision.

[The Woodlands]

Sweetie, since you have your eyes tested and the people told you that there isn't anything wrong with your eyes, there might be nothing wrong with your eyes. But I doubt that whether there is something wrong with your health. You know, I mean anemia or something else. Sometimes other health problems may affect our vision too. So you'd better have your whole body checked to see whether you need some medical treatment or not.