Hi welcome to Health care magic forum. As you describe it appears to be due to Filarial infection , Occur due to wucereria bancrofty infection. the infection is very acute, so you should immediately consult a physician for diagnosis and treatment.
For confermation you have to get the peripheral smear collected in the mid night. For this you have to use the drugs for a complete course for 20 days, along with anti inflamatories, and antibiotics, till you get the remmission of the symptoms.
Other possibilities could be some injury
to the foot, or arthritis
. Ofcourse the doctor will look after the possibilities.
Wishing for a quick and complete remmission and thanks for calling.