i suspect you may have a sprain ,however i suggest you to visit your doctor for clinical evaluation to eliminate possibilities of other causes(ie autoimmune illness).as you are a basketball/football player i uspect it may be a sprain(ie strech or tear of the ligament)
i give you some advice that will help and provide relieve :
Normally NSAID's and Analgesics are used to decrease pain and swelling.
Advil or Motrin twice/day for 5-7 days with Acetaminophen .
at present i suggest you to give rest to your leg muscles any vigrous movements can result in more inflamation.
apply ice pack (this will reduce pain, sweeling and inflammation in injured muscles, joints and connective tissues.
Compress the area with an elastic bandage until the swelling stops and don't wrap it too tightly or you may hinder circulation. if you feel the pain/swelling have increased ,just loose the bandage.
here's an excellent link by mayoclinic with some other methods of treatment.
if the symptoms still persist ,a consultation with an orthopedic or a sports injury specialist will be benificial in your case as manual examination by the doctor will help in predicting the prognosis and time for recovery
i hope this information is useful.
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