cough

hi mommies just wanna ask if its normal to have cough during pregnancy. i know our immune system is really low when pregnant. but i am already taking 1gm of vit c everyday. last month i already had cough and colds. and now im already in my 30th week i am experiencing dry cough which i know will soon lead to productive cough. hone remedies didnt really worked the forst time so i had to take antibiotics. am really worried to take another week of antibiotivs for this 2nd round of cough.