madam elevated TSH suggests hypothyroidism
where in which heart rate reduces and child would feel dull.
but in this case it looks more or less like a case of thyroiditis most commonly Hashimoto's. this would lead to hypothyroidism with bouts of hyperthyroidism
. it is in this hyperthyroidism phase where heart rate increases and nervousness
get the child's Anti TPO and anti thyroglobulin
done and keep me posted.