I developed a sudden pain and stiffness in my ankle and find it difficult to walk?

Need more info: That description isn't enough detail to provide a helpful answer. How long has it hurt? Did you injure it? Do you have a history of arthritis or other systemic disease? Is it swollen, bruised or does it click or crunch on movement? If rest, ice and time don't help, have it checked by a podiatrist or orthopedist. You might need an x-ray or MRI if pain is persistent.

Ankle pain: With no previous trauma or injury an appointment with a foot and ankle specialist sounds the right decision.