Woke up with vision sensitivity, as if there was flashing all around. after a few minutes my vision went back to normal.

Could be migraine: Some people have a visual migraine (visual symptoms with no headache) with flashing in the peripheral vision that resolves after a few minutes. Symptoms like this might also be from low blood pressure encountered right after awakening that resolves as the pressure normalizes. In both cases, there should be no risk to the eyes or vision.