Nrv probs in foot 4 years. Did lots of swimming. Hurts where leg meets foot/swollen in 4 places around ankle. Can hardly walk. Foot feels heavy/have to keep flat. I don't recall an injury. So much pain.?

Ankle pain. I might suggest you see a sports medicine orthopod. That specialist would determine what course to take ie. Bloodwork, x-ray, cat scan, and/or mri. That being said I am a psychiatrist and just suggesting what i would tell a family member if they called me with your question.
It's swollen . For a reason......Go visit a foot/ankle doc so they can evaluate.
Unspecific pain. Need your age and health status to properly answer.