I have been experiencing light flashes in mu room almost like lightning. Its not coming from outside or from any power outlet. Help.?

I suggest you go see an ophthalmologist. Problems with your visions are something not to be taken lightly.

Depending on your age, this can be a sign of a harmless eye condition. If so, it is more noticeable in relative darkness. In bright lighting, the ambient light masks the perception of flashes.

Light does not come from nothing. You could have a shorting outlet, a light bulb about to die, a sparking electrical cord, or you could be experiencing alterations to your vision. Turn off all lights and darken the room. If you can see flashes of light, but can't actually see objects illuminated, then you are having visual "flashes" and you should see an eye doctor as soon as possible.