is not diagnosed with ECG- if there is clinical doubt,one has to to Echocardiography
to rule out especially in view of sweating!
usually improves with time by 6-8 months.
Why ranitidine- may be a doubt of GO reflux?Is it needed?prolonged ranitidine is not good!
Regarding excessive sleep check for hypothyroidism
if screening test was not done at birth in your country.It is unusual!