Over the weekend I was bike riding, and after a long ride I was overcome with a sick feeling. I experienced the following symptoms, dizziness, vomiting, a hot then cold feeling in my head, like a rhythm, paleness and most disturbingly loosing about two thirds of my vision for 5/10 minutes. To describe it better, it was as if day turned to night. Since then I've felt decent aside from some anxiety, and experienced some chest pain now and then.
At school I experienced dizzy spells, after which I got a checkup with those plugs over my body with me lying still. That was about a year and a half ago.
I'd really appreciate any feedback as to what the problem it may be and thanks in advance!