At this time, you should consider returning to your surgeon to discuss your results since your higher breast probably won’t drop anymore. Revision may be needed.
Your one implant that appears to be sitting higher may need a revision to bring down the implant. You should see your chosen surgeon to discuss your options.
From your description of the sequence of events, it sounds like you may be developing a contracture around the right breast implant. Talk to your surgeon about implant exercises and the use of a band to put pressure on the top of the right breast. Sometimes a short course of physical therapy can work wonders. Best of luck.
Wait 6 months for the higher breast to drop more. Ask your surgeon about breast implant displacement exercises and a bando. Also make certain you are not forming a capsular contracture on the right. If after 6 months the higher breast is soft and moveable but still higher a lift of the lower breast may be needed for symmetry.
Thank you for your question and photos. It appears that your right breast hasn't dropped as expected. There could be a number of reasons so I recommend that you ask your Plastic Surgeon to examine you in person and advise you of next steps.
All the best
Submuscular implants have the added component of muscle contraction which can affect shape. Some patients require a plane change to maximize their results. You should discuss with your board certified plastic surgeon what options are available to you.