Any ideas?

My LO will be 4 months Friday and has a runny nose and cough but no fever. I'm messaging his Dr but bc thier closed today, I won't hear anything until tomorrow. I use Saline drops, syringe his nose, and have a humidifier in his room. I'm pretty sure the cough is from nasal drip bc the same happens to me (bad allergies). He doesn't really seem bothered by it. Just curious if there is more I could do to help the cough and runny nose before it turns into more?