I seem to have developed two dents in my cheek which are getting worse, could this be due to Botox?

I cannot think of a reason that you would have developed this depression on your cheek from Botox.  Botox can certainly cause soft tissue changes based upon muscle atrophy but unlikely to result in this indentation.  Have you had filler or any other injectable?  My recommendation is to be evaluated by a dermatologist or plastic surgeon so he/she may fully evaluate your medical history and physical examination findings. 
Not everyone is a good candidate for this treatment so please see a Board Certified or Board Eligible Plastic Surgeon to evaluate if you may benefit. Good luck!
This content is for educational and informational purposes only. It is not a substitute for medical advice, diagnosis, or treatment provided by a qualified healthcare professional.  You should always seek the advice of your physician or healthcare professional for any questions you have about your own medical condition. 

I think that your skin indent is not related to your Botox injections. It looks like your fat cells are unevenly distributed like with cellulite, however you should definitely see a doctor for consultation in person. You may benefit from Juvederm or PRP injection. 

Hello hello,
Thanks for the question.
There can be different reasons for this, Botox can potentially attribute to that. By any chance do you have any smiling before photos?
Warm regards :-)

Hi Pinkpuss, 
There is some volume loss associated with chronological aging. Collage, elastin, hyaluronic acid (yes, the same one in fillers) and fat breakdown and are not produced fast enough. Various parts of the face are affected. 
I would ask when your last Botox injection was and where the injection points were. Muscle atrophy seldom happens in that area but it has been ten years so it would be good to stop having Botox on the nose area (for now) although the forehead should be fine.
As for cancer, it is usually not symmetrical but DO get a second opinion. A doctor can check if the area underneath is hard or fibrous.
All the best,
Justin Harper, M.D.