It is normal to have some swelling after an injury. But if a large area of swelling occurs within 30 minutes of an injury, the swelling may be a sign of:
A more serious injury.
Swelling (edema) in the feet and ankles is common after you have been sitting or standing for a length of time. It is also common during hot or humid weather. Sitting or lying down with your feet propped up often relieves this type of swelling.
Mild generalized swelling of the feet and ankles is common in people who have varicose veins. For more information, see the topic Varicose Veins in Related Information.