3 month old coughing

My 3 month old has been coughing for a few days. I took her into the pediatrician for this yesterday and he basically said she was fine and he thinks she’s coughing on spit up/reflux. I feel like the reason he thinks that is because I had brought her in a few days before for excessive spitting up. I will admit I’m a little paranoid but I just don’t think that this cough is a reflux/spit up cough. She originally was only coughing when I would lay her down in a swing or something and I’d pick her up and she’d stop. So I originally thought maybe it could be from spit up/reflux but it seems like since the appointment the cough has changed? She’s been asleep on my chest for a couple of hours and she will occasionally cough. It’s a dry cough and I know that Google isn’t my friend but Google says when a baby younger than 4 months coughs that it’s serious.

I guess I’m just wondering if I should call the pediatrician again or if I should just let it be since he already said she’s fine? Anyone else had a similar experience? I just don’t want to overlook it thinking it’s nothing if it is something.

*they tested her for covid and RSV and both tests came back negative.