sometimes I see like a bright spot in my left eye.
2 or 3 minutes later I can see it again, but alsmot everyday I can see it.

is this like a flash (vitreus pulling the retina)? or other thing?
should I go to the eye doctor?

I have posteior vitreus detachment and floaters,but I had never seen a flash like somebody describes them.

Locatis,
Well it may very well be the vitreous pulling on the retina, causing the flash of light. If this is a new symptom for you, you should have your eye doctor examine your eyes. The vitrous pulling on the retina can cause a tear or detachment and best if you catch something like that early.
Anytime you get a new symptom, you should get it checked. Ann new flashes of light, new numerous floaters, etc should be evaluated.
Hellas