I am having swelling in my left ankle and leg. what could this be? i have pictures as well.

Ankle and leg: Are you having pain in the ankle too? Any injury, twisting? Are you a smoker? Take birth control? Had a blood clot prior to now? If the swelling came on without injury and involved lower leg, calf, I would want you to be seen by a doctor.

Below: The swelling could occur with a mskel injury, or could be secondary to more trouble some issues. Unable to give you an accurate DX without a hands on exam to check for pulses, edema, evidence of thrombosis. Suggest getting exam to get DX

DVT? Infection?: If not the result of injury, maybe a blood clot in a leg vein (thrombophlebitis, i.e. deep venous thrombosis, DVT). Or infection if pain, redness of the skin, tenderness to touch or fever. Both are serious, and DVT can be life threatening if a blood clot breaks off and goes to a lung. Even though it's Sunday, contact your doctor ASAP; if not available and nobody on call, go to ER or urgent care.

Concerning: It is concerning when swelling occurs in the leg and ankle without any history of trauma. The most important concern is the possibility of a blood clot. Since, left untreated, a clot could have serious consequences, it might be wise to have this checked out. Immediately.