Weird noise in lungs, but dry cough?

i had the flu and a dry cough because of my throat being irritated last week. then the dry cough turned into some phlegm, but that again went away. now i have no fever or any other symptoms, just this cough and my lungs are making a weird rattling noise at the ends of my inhalations and exhalations. i'm like, voluntarily coughing, it's not a reflex, to try to get this sound out. it works sometimes, but it's been like this for a few days. thoughts?