How much should I worry about a swollen foot?

Swollen Foot. Swelling is not normal. I would get it checked out by your physician.
Depends. If it has present for a long time you should see a doctor to find out the cause.
Swollen and worry. As stated , swelling isn't normal . See you podiatrist for an evaluation and don't be surprised if you have more than one doctor evaluating this for the cause .