It seems that you are having insect toxic dermatitis
Do not scratch the lesion.
If you have itching sensation ,take antihistaminics.
Take antibiotics if you feel having infection.
Take a short course of steroids
in tappering dose.
Avoid soap application on affected area.
Take precautions to protect the body from insects..
I hope you might be alright. Still, you consult dermatologist
With best wishes..
Dr. Ilyas Patel MD