This is my third surgery, I don't understand why this is not working out for me? Very depressing. I'm 6 weeks post op

It is impossible to comment on your situation without knowing more specific details of your surgeries and seeing pre-op photos. The best advice I can give you it to speak to your surgeon if you are unhappy. If you choose to seek another opinion with another surgeon, make sure to bring all your medical records with you for review. 

To give an informed answer to your questions and concerns, it would be necessary to have your original pre-op photos and prior operative notes from all surgeries, to understand exactly what was done and what type of implants you have.  If your implants were only moved from a submuscular position to a subglandular position, there should not be any change in volume.  Possible causes, if you have saline implants, is a slow leak of the saline in the smaller side or a fluid collection in the larger side.  You should return to your surgeon and express your concerns so this issue can be resolved.  Best wishes.

More details about your previous surgeries would help. Sometimes the muscle is thicker on one side than the other and this  may contribute to the overall shape and size.