ocular auras? please help

sad  Hi
Just wanna firstly say this site is really great :)
Has anyone ever experienced an ocular migrane that lasts for no more than a minute or two? I have experienced cloudy patchy vision of a pale colour that then quickly turns to  "heat waves" of lights that begin in my left eye then gradually move to my right but fade out after a few minutes.  I find that these light shows generally occur after I have compromised my posture or when my eyes are strained and tired. Is it normal for ocular migranes to just occur for a few minutes? Is it possible that a person can enduce thes occurances by placing their head a certain way? I have noticed that they can begin if I have been lying on the couch with my head against the arm rest or even when lying in bed with my neck on a certain angle.  Can anyone lend some advice? I never ever feel pain with these disturbances. I am 27 years of age and they only started occuring over the past 12 months.  I have probably in total experienced about 7. I feel so unsure and confused :(

OVER THE PAST 40 YEARS I HAVE HAD 1,000'S OF THESE AURAS. THE FIRST 7 YEARS THEY WERE VERY PAINFUL MIGRAINES THAT LASTED FOR 2 DAYS. NOW THEY ARE A BEAUTIFUL LIGHT EXPERIENCE THAT LASTS FOR ABOUT 20 MINUTES. THEY CHANGED FROM THE PAIN TO THE BEAUTIFUL I 1 20 MIN. MEDITATION SESSION. NOW I CONSIDER THEM A GIFT, AND MISS THEM IF THEY ARE GONE FOR TOO LONG. I HOPE YOU CONTINUE TO ENJOY YOURS.

REGARDS - RVB3D