Sorry I could not trace your previous query.
But from what you say, I guess he had a viral gastroenteritis
And now you feel he has recovered but just is tired and he feels cold and clammy.
What is the outside temperature? If low and if your kid is not dressed adequately, he might be pale and cold. Cover him adequately. Use socks, gloves, caps etc if outside temperature is low. But tiredness
will not happen in such a case.
How is his food and fluid intake? If he has just recovered from diarrhea
and if fluid intake is not sufficient, he might have these symptoms.
Normal temperature is 98.6'F. So he does not have fever.
Give him plenty of fluids, fruit juices, soups, flavoured glucose drinks etc.
Keep an eye on the frequency of urine.
If he continues to be tired/ urine frequency is very less or his cold clammy nature does not improve at all , you must see your Pediatrician
to rule out hypovolemic states.
Hope my answer helps you.
Wish a speedy recovery for your kid.