Ok thank you all, for your response to my thread.
Well i had visited an eye specialist in my area, he checked and i told him about my issues.
He said I had slight less visibility issue in my right eye and recommended glasses.
He checked with his equipments and said there was nothing major issue with me eye site or internal eye structure.
The flashes were may be migraine related he said.
I m still confused because some times i see colors mostly when i have headaches.