One eye is bigger than the other, what can I do to fix this? It seems to have gotten worse. (Photo)

For this reason, you would benefit from surgery on both sides.  When only the heavy eyelid is addressed surgically, after surgery the good eye will then appear heavy. When the droopy eyelid is fixed, the eyebrows will relax to a more natural position.  You also have eyelash ptosis and a high crease.  For this reason you are likely to need an anterior levator resection ptosis surgery with an anchor blepharoplasty to make a new hard upper eyelid crease.  While surgery is comfortable, it is best under light intravenous sedation.  That means performing it in a accredited surgery center rather than in a back office procedure room.  Most people take a week or ten days off of work but you will feel fine to be on the computer and phone in a day or so.  The surgery wil give you a jewel like quality to your eyes restoring them as your best facial feature.

You have asymmetric upper eyelid ptosis (droopy upper eyelids). You would likely benefit from upper eyelid ptosis correction which can be done under local anesthesia with hidden incision. See an oculoplastic surgeon.

Your left eye looks smaller than your right eye because you have eyelid ptosis (drooping of the eyelid).  This is a problem that can be corrected with outpatient surgery.  Your best bet is to see a surgeon who specializes in eyelids for a complete evaluation.  He/she can review the best options for you. 
Hope this is helpful.