Thanks for writing to h.c.m.
I have gone through your query regarding enlarged painful lymph
nodes behind ears on either side associated with infective lesions on scalp
and an indentation on back of head which is also painful.
This all indicates that primary infection of scalp is responsible for enlargement of draining lymph nodes , which are located behind the pinna of ears.
As for as treatment is concerned you may take-
2- Anti inflammatory.
I hope this will help you, otherwise you may consult your family physician for thorough examination and treatment.