abdominal pain since 45 minutes

I was very hungry.

It started to hurt at half way my supper.
My stool is green and skinny, long as 15-20cm.
I'm 24, low blood pressure since at least 10 years ago.
I have vertigo once in a while. (vertigo for me is like: the world starts spinning, when I open my eyes, the world turns around me so I have to keep my eyes closed or I feel like vomiting more quickly)
At 15-16 years old, I had a terrible headache with vertigo. made me scream all night.
No allergy from my knowledge.
I might have anaemia, but it is only my guess.
In the morning, my face skin tone is a bit yellowish and dark brown compared to other members of my family. But at night, my skin looks normal... or even healthier than the others.
I never had surgery.
I have a short breath. I weight 45kg and 1m60.
I feel like I had not enough sleep these days. I feel often tired and sleepy.
At the moment, my eyes are itching and burning. My face feels warm, but when I touch it, it is cold.
I had lot of stress these past few years.
I spend quite a lot of time in front of the computer. It became a habit to spend time in front of a computer.
During all my high school, I spent almost 24h/day in front of a computer or near them.
I worked at the internet cafe.
At that time, I had a terrible abdominal pain that lasted for long hours and caused vertigo.
It was so painful that I couldn't breathe properly, nor think, nor move.
Right now, as I am still writing, my central abdominal is burning also.