Baby cold

My 4.5 month old has another cold but it seems worse then that? He’s super snotty, he keeps coughing and then gagging on the end, he can’t breathe at night he’s snoring/mouth breathing right now bc he is so congested. He won’t sleep in his crib he cries if he’s not with me. I also noticed he’s not eating as much, it might only be a couple of ounces and maybe I’m just an overanxious FTM. But does anybody have any advice? I’m so worried about him. He prefers bottled breast milk and at the moment I can’t even let him suckle bc I’m on a steroid due to a bad allergic reaction I had. They wanted me on it for 5 days but I’m about to cut it short after 2 days if it’ll help make the baby better.