2 weeks after Botox, my midface and smile are totally different. Did Botox cause my sagging cheeks? (photos)

Thank you for your question and for sharing your photographs Melissa1213. I understand your concern. Botox is a purified protein used to address wrinkles associated with facial expression. When injected into the skin Botox will relax the muscles and smoothen out the overlying wrinkles. The most common areas of treatment are in the upper face. These include the horizontal lines seen on the upper forehead when one raises the brows, the vertical lines seen between the brows when one frowns (frown lines), and the crow's feet seen around the eyes when one smiles.
It is difficult to make an assessment without a formal exam in the office where I can view the skin in multiple angles and observe wrinkles formed with facial expression. However, I hope the information provided here is useful.The pivotal studies used 24 units of Botox (12 units per side) to address the crow’s feet. These studies demonstrated that the peak results are seen 14 days after the treatment and most people enjoy their results for 3-4 months. At that point, a maintenance treatment is recommended. While some people start to see results as early as the next day, it can take two weeks for full results so patience is important. We have our patients return two weeks after their treatment to assess their results via photographs. At that time additional units may be added if necessary. 
Botox can be placed in the masseter muscle in the lower face to contour the lower face and address pain associated with TMJ. In this area 20-40 units of Botox are used per side. Depending on the reason for the enlargement of the muscle, permanent results may be achieved. For example, some people have a habit of grinding, clenching, or biting their teeth subconsciously. Often times this happens in their sleep when they are not aware of it. Botox placed in this muscle will relax the muscle and the grinding, clenching, and/or biting will decrease. This will reduce the size of the muscle. If the brain gets accustomed to this and the person stops grinding, clenching, or biting, then the muscle will not become enlarged or as enlarged again. However, if the habit starts again, the muscle will likely get larger.

To determine if someone is a good candidate for this treatment it is necessary to look at a person’s lower face when biting and comparing it to when the person is not biting. If a bulge is seen on the outer portion of the jawline, then the person is likely a candidate. It can also be felt with the fingers when biting.
In the mid face, the zygomaticus muscles sit just below the orbicularis oculi muscle which is treated to address the crow’s feet. When smiling, the zygomaticus muscles pull the corners of the mouth upward. If Botox spreads from the orbicularis oculi muscle downward toward the zygomaticus muscles, these muscles can also become relaxed, leading to the appearance of an asymmetric smile. This side effect resolves on its own in 2 weeks to 4 months, depending on the severity. Some find that laser skin tightening treatments using infrared light or radiofrequency may speed up the resolution process.
In the mid face, the risorius muscle and zygomaticus muscles sit near the masseter muscle which is treated for TMJ pain or to contour the lower face. When smiling, the risorius muscle pulls the corners of the mouth outward towards the ears and the zygomaticus muscles pull the corners of the mouth upward. The masseter muscle is used to bite down when eating. If Botox spreads from the masseter muscle forward toward the risorius muscle or upward toward the zygomaticus muscles, these muscles can also become relaxed, leading to the appearance of an asymmetric smile. This side effect resolves on its own in 2 weeks to 4 months, depending on the severity. Some find that laser skin tightening treatments using infrared light or radiofrequency may speed up the resolution process.
If I had a patient with the concern described here I would say that either the zygomaticus muscles or the risorius muscles have been affected and it looks like both sides were affected approximately evenly. Fortunately this is not permanent and treatments described above may help with the resolution process.With any injection, there are risks such as pain, bleeding, bruising, redness, swelling, tenderness, and infection. We take special precautions to minimize these risks such as using a painless technique. We also treat bruises with a laser as early as the next day. Bruises usually resolve within two weeks if untreated. After a laser treatment bruises usually resolve in 1-3 days, but may still take two weeks for full resolution. In addition to these risks, with Botox there is also a risk that the product spreads or diffuses to nearby structures. Spread to nearby muscles can lead to side effects such as the temporary appearance of droopy eyelids or a temporary asymmetric smile.

After a Botox treatment, I recommend that my patients avoid heat exposure, alcohol consumption, and strenuous exercise for 24 hours and not lie down flat for four hours. This is because all of these activities may possibly lead to the movement of the product and consequent side effects such as droopy eyelids. Although there have been no definitive studies shown that these actually occur and some physicians do not provide such aftercare instructions, in the absence of data I err on the side of caution and recommend that my patients avoid such activities.

Please consult with a doctor for specific recommendations. Good luck!

So sorry that you are experiencing this - There is definitely a noticeable difference between the two photos, so I am surprised to hear that your injector did not notice this.
Absolutely, your face will return back to normal. Unfortunately, with Botox, there is nothing you can do to reverse it besides wait it out until it wears off.
Next time, perhaps go lighter on amount of units :)
Best of luck!