There is a difference between the 2 sides of the face that is normal. It usually becomes apparent in the early twenties and becomes more noticeable over the years. It’s because we all have a dominant, stronger eye. When you look at newsreaders on television, you will notice that you are preferentially looking into one eye, their stronger communicating one. This information comes from my experience in facial surgery, which requires so much observation. So many people request correction of a difference of the brow height or difference of the upper eyelid at the time facelift surgery. Patients are surprised to find that the 2 sides of their face are not a matched, mirror imaged pair! Usually it is the left side of the facial skeleton that is smaller, centered around the eye, involving the bone of the orbital cavity as well as the surrounding bone of the brow and cheek., Because the eyeball is deeper set the left eye seems smaller as well as sitting lower down than the right. Because the cause is the bone structure and because the eyeball is the central part of it, there is little benefit from building out the bone to match the other side, because the eye doesn't move and visually, the eye difference would become exaggerated. You will find that other people do not notice what you see, just as you have not noticed this on other people! This is partly because its detection requires specific analysis, holding the head still as you do when studying your face in a mirror. Also, because we are subconsciously attuned to people having a weaker side. The short answer is that, at this stage there is nothing to be done. Later, in life, if you have some facial rejuvenation surgery, some camouflage adjustments could be included that reduces the visible difference of the brow height, the upper lid fold or the cheek prominence.