Could eye flashes caused by filler injections?

Flashing lights in your peripheral vision can sometimes be a sign of a serious eye problem. See an ophthalmologist as soon as possible.

Flashing lights are not a normal side effect of injections. Schedule an appointment with an ophthalmologist and obtain an assessment. Best of Luck.  

I suggest seeking an immediate evaluation.  Any change in vision following periorbital filler treatment should be taken seriously.  There are many cases of filler occluding vessels of the nose and eyes causing permanent damage.  Not trying to scare you, but a formal evaluation should be done to ensure this is not something serious that would otherwise not be able to be treated if not caught early.  Best, Dr. Emer.