Swelling in the foot can be caused by wearing inappropriate shoes, engaging in certain sports activities like running or walking, or having a foot problem. To reduce the swelling, you can apply ice or take an anti-inflammatory medication like ibuprofen if you have no contraindications. If your foot becomes painful, red, hot, or more swollen, it is advisable to see a doctor. If the swelling does not improve within a week, you may consider consulting a podiatrist. You can use the following tool to find podiatrists in your area: https://piedreseau.com/cliniques/ Hopefully, this addresses your concern.