coughs

when should I take my 11 week old in for a cough?

I called his pediatrician on Thursday when it became noticeable, but they told me just use a humidifier (which i feel has no affect what so ever) this morning he woke up coughing a lot more than he has these past few days.

Ima first time mom so of course im going crazy worrying..

& to top it off i have an extremely sore throat.