Thanks for the query.
You might have developed scar eczema
Another possibility is a bacterial infection.
Treatment with oral and topical antibiotics is required.
A culture from the oozing fluid will help in finding the exact causative organism,
Please meet a dermatologist
for exact diagnosis.
Let me know if you have any other doubt.
you can ask a direct question to me on this forum, following the below link.
Wishing you a good health.