SOme asymmetry is normal as you can see from your preop photos and the folds are not always the same. But you are only 4 weeks out, and you should give it a few more months.
No patient is perfectly symmetrical. With that in mind, you are only a month out from surgery, so try to be patient as it can take 2-3 months for implants to settle and your breast to change shape. Go see your surgeon for a follow up visit and let him/her know about your concerns. At that time, perhaps ask about wearing a band to help the left breast drop or aggressive massaging. It is common for breasts to contract and appear deformed when flexing but when not flexing they should go back to it's previous relaxed state. ac
You are still early in your recovery and based on your photographs my guess is that your breasts will continue to drop.
However it is important to follow up with your plastic surgeon for advice and not rely on online advice.
Ask your plastic surgeon if massage or breast implant displacement exercises may help.