1 month old caught a cold?

Abby
Thrusday my mom took my soon to my granny's where my step cousin and my uncle and her mom lives and apparently my cousin who is 8 was kissing all over him 
And then Friday she got sent him from school cause she was sick🙄😡 now my baby is showing signs like stuffy nose and he has green gunk on his eyes when he sleeps im calling the pediatrician tommorow but I was wondering what I can do for him in the meantime he's so stuffy it sounds like he's snoring when he sleeps