blue/purple dot on facetime

Nina

okay so i’ve noticed this for a few months and it is EVERYTIME i go to facetime someone. it’s a smal blue/purple blinking light when i’m ringing to facetime someone. it’s never there when i’m just on my phone or when they answer. here’s a picture.

if you look on the right of my forehead you can see it. the dot never moves spots, not with lighting or anything. it’s so weird.

what is it?