Thanks for posting your query.
Congenital insensitivity to pain with anhidrosis
(CIPA) has two characteristic features: the inability to feel pain and temperature, and decreased or absent sweating (anhidrosis). This condition is also known as hereditary sensory and autonomic neuropathy type IV. The signs and symptoms of CIPA appear early, usually at birth or during infancy, but with careful medical attention, affected individuals can live into adulthood.
Normally, sweating helps cool the body temperature. However, in people with CIPA, anhidrosis often causes recurrent, extremely high fevers (hyperpyrexia) and seizures brought on by high temperature (febrile seizures
I would recommend you consult a genetics specialist
or rare disease centre in a multispeciality hospital in your vicinity for a thorough evaluation and diagnosis .
Please do not label your child before any formal diagnosis which might require investigations like EEG, MRI
As for sleep pattern it's best to consult a sleep consultant if it's really disrupting your child's life.
Hope that answers your query .