Sometimes when I go into another room, maybe with a different lighting I see black for a second. For example, today I got up off my couch and walked into the bathroom and I could feel it happening for a couple seconds and when I had looked in the mirror I saw black, I couldn't see my whole face, but some was visible, then it went away and everything was normal.
I was just wondering if this happens to anyone else sometimes.
For me it's not constantly happening but it happens frequently but only for a second when it does.
Is this a sign of low blood pressure or something [mine's always normal.] Btw I am 15 years of age.
Thanks for everyone who helps me by answering!

You need to see a Physician.

Thanks I may. I notice it's when I'm on the computer or watching TV and if the lighting is different in another room sometimes so maybe it's just the blood rushing back for a second.

My mother and I talked and it may be because I don't always eat and drink enough, and also for people my age blood pressure can quickly drop and go back like that. So it may just be both of those. Although if it get's worse we will get it looked at just to be safe, because my mother had these symptoms once and had a seizure, although my are not bad. So I'm just going to eat more and drink enough and be careful.

I saw floaters yesterday for about 2 minutes.
Why does that happen?

You need to see a doctor to get your blood pressure checked. This sounds like it could possibly be orthostatic hypotension.

That basically means that your blood pressure drops when you change positions such as from sitting to standing.

I actually just realized I thought I had that, and I talked to my mom about it. It has been fine lately, I think I have to make sure I'm not dehydrated and am eating enough, because when it had happened last, I may not have been taking as good care of that.