12 month old throwing up and coughing at night

Jenn • Beautiful boy born 5/21, expecting second 4/23

Hello! My 12 mo old has been coughing only at night while sleeping for the past 6 weeks and recently in the past week has started coughing so hard that he throws up 30 minutes after he goes down. It’s affecting his sleep and mine and I just feel terrible that something I’m doing is making him feel sick at night. Could it be acid reflux? Food allergy? He eats dinner at 6 and then bed by 7:15-should dinner be earlier? Any advice is appreciated!