Last night after studying, i got tunnel vision, got extremely nauseous, vomited, and druring this episode, i had the smell of blood or metal.

Migraine likely: Sudden onset of tunnel vision, nausea and vomiting and peculiar smell would likely be a migraine attack. With such a migraine a headache would often (but not necessarily)follow. A less likely but possible cause would be a seizure. ***It's very important that you discuss this event with your physician or with a neurologist to be certain of the diagnosis and to exclude other possible causes.