Help

I just became a vegetarian three days ago. I'e been eating 6 times a day, veggies, fruits, brown rice, beans etc....
I now as I have for the last month run two miles 6 days a week on a tredmill first thing in the morning.
The problen is: by noon or 1:00 I feel light headed, my eyes go blurry, I feel High. Is this how I'm supposed to feel, and have been missing out? Or maybe with the exercise I need to consume more calories? It's like I eat all day long. Or is there some adjustment period? Please Help? Tweet