and ankle pain
can be caused by a variety of causes.
I agree with the treatment for DVT. Other potential causes can be infection, osteoarthritis, sprains or bursitis. Imaging the joints can be considered with, first, a plain film, and second, an MRI can be considered.
If negative, more systemic causes can be considered, including evaluating the kidneys with blood tests, and the heart with an echocardiogram.
These options can be discussed with your personal physician.