Brief Answer:
Bug bite

Detailed Answer:

Hello,

I have gone through your query and also through the attached picture. It less likely to be a mosquito bite but more likely could be any bug bite.

I would suggest you to do the following:
- Clean the area with soap and water.
- If there is any associated itching, you can apply calamine lotion topically over the affected area and you may also choose to take anti histaminics like cetirizine for 2-3 days.
- For the localised pain, you may apply topical cortisone cream for 2-3 days.
- If any signs of infection, you can use topical antibiotic like polymycin or neomycin ointment.

I hope this helps,

Please feel free to discuss further or else kindly close the query with a positive feedback.

Regards

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