Why are my eyes different shapes and how can I fix this? (Photo)

Eye asymmetry is common. It appears your right eye and orbit is larger than left and lower eyelid is more retracted than left. See following website link for more information on eye asymmetry and possible solutions.

A personal assessment is needed to determine the best surgical approach for this.  I routinely operate on small amount of upper eyelid ptosis.  Study my before and after photos to understand what is possible in addressing these small differences and the power they have to make you look your best.

The position of the upper and lower eyelids are slightly different between the two eyes.  Causes may include different position of the eyes in the bony orbit relative to one another, difference size/ shape of the eyes, eyelid retraction due to systemic causes, or droopiness of the eyelids.  The cause and the treatment can be determined with an in person examination.   

 Everyone has some degree  of facial and eyelid asymmetry, which is normal. The degree of asymmetry from the one limited photograph is very minimal at best. Best to leave well enough alone, no surgery is indicated

Good Day. Thank you for your question, narrative and photograph.
You are a beautiful woman with wonderful eyes.
The amount of asymmetry is negligible to my perception and no revision is necessary. Subtle changes can be performed after an unperson consultation to determine exactly your desires.
There is a risk to every procedure. The risk is probably not worth the amount of aesthetic improvement that we could attain.
My recommendation is to do nothing. 
Have a wonderful day.

It is normal to not be totally symmetric. We are always our worse critic and this asymmetry is most likely only apparent to you.
Dean Vistnes.
Vistnes Plastic Surgery 
San Francisco Bay Area