Hello,
Thanks for your query at DoctorSpring. I can understand your concern.
It seems to be a an insect bite. I would recommend that you take an anti histaminic tablet like loratidine 10 mg once a day and apply mometasone cream twice a day for a week.
The cream would require a prescription.
Cortisone is a mild cream, hence you would require something stronger.
The tablets are available over the counter. However, if within a week you don't get relief I would request you to visit a doctor who can examine it physically.
Please let me know if you have any queries.
Take care