2 week old coughing / gasping at night

My 2 week old has started coughing up a lot at night and im not sleeping at all because it scares me so bad sounds like hes choking

I just took him to the dr yesterday because he was making horrible wheezing noises that sounds like a creaking chair when he breathes out and the doctor said as long as he doesn’t turn blue he’s fine and it’s just normal congestion.

But now he’s doing this coughing at night. And he doesn’t really do it during the day. He’s combo fed so idk if it’s the formula but why just at night when he eats and sleeps the same during the day?

Anyone experience this?? Idk if I’m just being overly worried or I should bring him back.