Hello! My 1 Year Old Had A Cold 2 Weeks

Hello! My 1 year old had a cold 2 weeks ago, now he seems fine,he only swalloes his mucous/phlegm, but I heard that is fine, the only thing that i don't know if it's a problem is that he keeps on waking up at night coughing on and on until he crys, should I take him in for a check up? Back then, after the cold, his pediatrician sayed to not give him anything, to let him be, but to me it seems we are not getting anywere because I don't see him getting better from this cough soon( he coughs during the day too, but not so bad as during the night, in rest he eats, drinks just fine)