At night keep the foot raised on pillows. Add
anti-inflammatory like ibuprofen to
anti allergics you are taking. If it has been more than 10 years since your last tetanus booster get a booster as soon as possible. If the swelling still persists after 72 hours and shows no sign of going down, then consult a doctor.If the reaction you had in the past was severe then immediately consult a doctor. If by reaction you mean localized swelling, then that is normal after a sting.
Hope this helps.