From your photos it looks like the right might be bigger so since you are only 7 weeks you can wait but since they are saline it would be easy to let everything settle down and then if need be go back and add a little saline to the smaller side.
Appears as serious mis diagnosis to what you needed. Best to seek in person second opinions...........
Based on your pre and post operative photos I understand your early concern. It appears that either the left implant has developed a capsular contracture and moved upward or the right inframammary fold region has overly settled downward. At this point I recommend you be patient, continue to follow up with your surgeon and see how the appearance evolves over the next several months. Early intervention at this point would be contraindicated. Be patient and best wishes.
Hang in there! As long as the shape and feel are improving week to week, however slowly, there is still hope for the final outcome. Ask you plastic surgeon if there are any compression garments, stretches or massaging exercises that can help speed your recovery.
I would agree with the other opinions at this time. That is to say, implant position will change during the first few months following surgery. sometimes one can improve this by making sure the implant is massaged throughout the pocket as well as stretching the muscle and having good range-of-motion of the arms and shoulders. That being said, i would recommend you continue closely with your surgeon so that any persistent differences can be addressed to your satisfaction.
Your concern is understandable but you are still very early in the post operative period. I inform my patients that the breasts can continue to change shape for up to 6 months or so after surgery. Many times, in that time frame, asymmetries do improve. I would encourage you to keep in contact with your plastic surgeon and be patient. That's not always easy, I understand, but it is necessary until you are fully healed.
Looks like your left has not dropped yet which when you have two sides, this can usually happen. One will fall faster than the other. There are bands that your surgeon can recommend for you to wear to help facilitate it dropping faster. Also ask about massaging techniques as well.
I can see why you're concerned and there is certainly no guarantee that symmetry will be achieved over time. Nevertheless this is early in the course of convalescence and the possibility exists that the situation may improve significantly. Continue to be patient and follow the advice of your surgeon.