You're sure that something bit you ?
Looks like allergic reaction to bite.
Tie a crepe bandage on swollen area
Next Steps
Take antiallergic tablet like Phenargan twice a day for 3 days
syrup Phenargan equally effective
don't take more than a spoon of syrup
Health Tips
reduce intake of the salt and drink lots of water will remove collected water in body through extra urine.