Once, after i ran i had faintness, difficulties in breathing, seeing (white image). then the medic gave me glucose and calcium, what were they for?

Two of the most: important and "urgent" reasons for your symptoms...low blood sugar and low calcium. Hope this helps! Dr Z

Suspected low sugar.: in the short term, low blood sugar is more dangerous than high level and so rapidly giving sugar for suspected symptom is a safer bet. I doubt that u had low calcium--as u likely would have experienced muscle spasm etc...but giving u some MAY reduce the risk of cardiac rhythm trouble. I would recommend checking with doc to see why u had trouble breathing...?asthma? Good luck