perhaps hallucination is too strong a word, but after i exercise i seem to see distortions in my field of vision...most notably when i look at something about 20-30 feet away, it seems to be drifting away from me. like there's a black hole in the center of my vision that's pulling everything in toward it. this is especially vivid when i look at a street: there's a very clear sense of the centerline sucking the edges of the street toward it. sometimes it's shocking how real it seems.
yeah, naturally this worries me. could i simply not be eating enough? i am a bit underweight, but i eat around 1600-2000 calories a day, usually pretty balanced, natural food(though i could stand to eat more vegetables). i'm a 20 year old male. i don't take any drugs or medications, drink very seldomly and i smoke a little.
oh, and when i say exercise, it isn't even necessarily heavy exercise. i could simply be riding my bike around town on a hot day when this happens.
can anyone help me? i don't want to arrange a doctor appointment if it's something simple.