I agree with Dr. Moelleken on a couple of accounts. First your right eye is more prominent and your left eye sits lower in the face than the right eye. However, it addition to these issues, the left upper eyelid rest about 1 mm lower on the globe than the right upper eyelid. This contributes to the left eye looking smaller. Ptosis surgery has the potential to improve this.
However, it is not normal for this type of small difference to be socially crippling. When these feeling exist, it suggest the presence of body dysmorphic disorder. Other signs would be abnormal preoccupation with these differences. An example would be spending hours a day obsessing about this problem. It is my expereince that there is no surgical cure for body dysmorphic disorder(BDD). The BDD brain is organized different than normal brains. This makes it very difficult to surgically help individuals with BDD because once one issue is improved, the brain will focus on how the fix was not every thing that was desired and as a result the person feel social incapacitated by embarrassment.
The best place to start is with psychotherapy to better understand why the brain fixates on these issues. Once you have insight regarding the BDD, it is usually easier to address the issues that benefit from surgery.