Perspiration is normal when temperature comes down. This is due to loss of temperature from body following dilatation of cutaneous blood vessels.
Repeated chest congestion with stuffy nose may be allergic or viral. Fever
is common during viral infection. If there si family history of allergy
then it goes in favour of allergy.
Low calcium and hemoglobin
is very common in infancy nowadays. This is mainly due to vit. D and iron deficiency
So I would suggest you to continue the medication prescribed by your doctor and also get a iron profile and serum level of vit. D level done after consulting your doctor. Iron, vitamin D and calcium supplementation may be needed accordingly.