Is it normal for one side to always be a bit bigger when you get filler in cheeks?

I get filler in my cheeks, side cheeks for contouring, but even when my doctor works to make them symmetrical, it seems that one side is always bigger, where they put more filler in one side more... is the asymmetry normal ? It seems twice already one side is bigger than the other... is it the injectors fault ? I do remember looking in the mirror at the one side which is smaller now looked bigger in the chair.