Is it necessary to see a podiatrist for an ankle that is very swollen and hurts?

Depends: Depending on where you are a podiatrist may not be able to treat your ankle swelling. It varies from state to state. But if your state allows it, you would benefit from having a podiatrist or another doctor examine you.

Have it evaluated.: See your primary physician and get the appropriate referrals. Both a podiatrist and a foot and ankle orthopedist can help you out.