Thanks for the query,
You have developed an eczema
secondary to lice infection.
It will be better to go for an application of permethrin.
Also take an anti histamine
This will control the itch.
Once lice is controlled your scalp
Please meet a dermatologist
for exact diagnosis.
And get the medication prescribed.
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 good health,