Thanks for the query,
You might have developed an eczema
which has got infected.
Treatment can be with oral antibacterials as well as with topical antibacterials like mupirocine..
Also take an antihistamine tablet.
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.