What could have caused my uneven eyes and how can it be fixed? (Photo)

Looking at your photo, your left upper lid does sit a little bit lower than the right one.  As others have pointed out this may be a result of a weakening of the muscle that lifts the lid, possibly related to contact lens use.  Additionally, your lower lid rides a bit higher than the right side as well.  There is a condition known as Horner's syndrome that you might have been born with but was never recognized that can give this same appearance. I would go see an oculoplastic surgeon for a further evaluation.

You may have a mild ptosis and mild brow ptosis on the left side.  The orbital volume appears slightly smaller on the left side as well.  The eyelid lifting muscle on the left could be slightly stretched from being a contact lens wearer.  I would consider consulting with an Oculoplastic surgeon in person.  You can discuss your concerns with him or her and come up with a plan vs. observation.  This does not constitute official medical advice.  Good luck.

Thank you for your question regarding uneven eyelids.  This condition is typically related to a stretched or partially detached upper eyelid muscle.  This can be present from birth, associated with aging, trauma, acquired over time or other eyelid diseases. The first step is to rule out any other conditions.  Surgery to tighten up the muscle can be performed to make the eyelids more even.  Best wishes.