Talk to Pediatrician on Nasal/chest Congestion And Fever

My son is 8 months old he started to have loose motions which turned out that he was on teething but he had constant cough along with nasal and Chest congestion...his loose motions are ok now but his cough still persist not much but it is still there but nasal and chest congestion stands the same and at times he gets fever as well which around 100 I have got his blood cp which came perfectly fine and doctor also recommended for thyroid gland test which also came out to be perfect he is taking his feed properly and takes cerelac as well without any issue kindly if you can give ur worthy opinion regarding this issue