I seem to have lost you.
Based on the information you have provided, the commonest and most worrying cause of inflammation in a joint, in your case an ankle joint, is infection.
Infection in the joint needs urgent treatment, usually a surgical drainage of the pus. The longer the pus remains in the joint, the worse it is for the joint cartilage. The long lasting effect of infection in the joint is arthritis.
Therefore this needs urgent assessment with blood tests (complete blood counts, ESR and CRP which are infection markers) and an ultrasound scan of the ankle to look for excessive fluid in the ankle joint.
While I am not suggesting that you have infection in the ankle joint at present, the only way to be sure is by assessing the joint. You therefore must visit your local A&E department or at least an urgent care walk-in centre.
The second common cause of ankle swelling and inflammation is an injury with resultant sprain. While this does need assessment and treatment, it is not as urgent as infection.
The rarer causes include viral infection, inflammation of synovium (lining) of the joint, etc. These need symptomatic treatment with anti inflammatory medications such as Ibuprofen and paracetamol.
Please let me know if you have any further questions here.