Cough 5 month old

My daughter has had a cough for a little over a week now. When it started, she had a ton of congestion. That has since subsided. We took her to the pediatrician last Monday and he said the cough was not in her lungs and was just caused by the mucous drainage. They told me to call them if she developed a fever or got worse. I called them Friday because she hadn’t improved and they said it just has to run its course.

Even though her congestion has improved, this cough won’t leave! I’m worried, it just sounds so forceful when she coughs. We’ve been giving her Zarbees, putting baby Vicks on her and doing suction when needed, but I just don’t know if I should take her back to the doctor since they seem to think she’s ok. Thoughts?