I wasn't sure where to post this, but eyes seemed like the best place.
This morning I had a nose bleed, and pretty much immediately after it stopped, I got a little lightheaded and my vision started going dark, until it was completely black. My balance, body control, and other senses also became kind of messed up. I had a hard time thinking straight, and ended up panicking. Once my vision started to come back (and the other symptoms faded), I noticed that I felt rather cold and I was covered in sweat. When I looked at myself in the mirror, my face was extremely pale and my lips were nearly colourless. I also had a second spell a few second later, but didn't completely black out.
I have had very similar experiences after I have had an immunization shot. This time there seemed to be no reason for it, except for maybe the nose bleed. It wasn't a particularly bad one, though, and I have never experienced any sort of vision loss from having one.
Any help would be welcome.