An explanation for Cortisol, not corisol, can be found here http://en.wikipedia.org/wiki/Cortisol
As you will see Cortisol is associated with an increase in glucose, not decrease. You should ask for a solid explanation as to why your doctor wants this tested and for what reason. And why he/she doesn't suspect hypoglycemia as the cause of your problem.
Are you sure about the 32 mg/dl reading? That would make one unconscious or close to a coma.
Inquire about your pancreas being tested and also for an insulin resistance test. An A1c test will verify your glucose levels.
Good luck.
yes I've been to the doctor and had a 6 hour glucose test which they had to stop at 3 hours because my bg went down to 32, but now they want to test for corisol? Which I don't understand what that is for?
Have you been to the doctor? If not, I suggest you go and be checked out
Only after lunch, no other times? Hypoglycemia is possible. See a doctor, get tested, learn what's happening to you.