Hi doctor, yesterday I took blood test for skin related problem in skin clinic. After they took blood within a minute my head started dizzy and while sitting itself I felt uncomfortable and lean backwards on seat. I felt like I was in dream, after a minute I woke my eyes up and its full black. I can not see anything even when I open my eyes fully. Its look full black, then I ask water to nurse. I drink water again and again and after a minute the black in vision started fading and I can see everyone around me little by little. The nurse keep on saying, "its nothing its nothing. Its happen just becoz you are afraid" but I do not think im afraid. I just saw the injection when they injecting and sucking the blood. But I do not think these things happened to me just becoz I saw the injecting needle and sucking blood from me. Why this things happen? What I experience? I felt like I went to some calm place. Omg! different experience. Black in my vision is terrible. Still im thinking, what it would be?