Thank you for your query,
This hearing sounds loudly of normal sounds is called hyperacusis and as it is associated with left temporal pain, there are two possibilities like
2. Auditory nerve and inner ear relate problems like, facial nerve palsy
, vestibular problems.
So I advise you to consult your Pediatrician
for the evaluation and referral for ENT specialist
and a Pediatric neurologist
Hope I have answered your query.