7 month old vomiting

So we just came off antibiotics for a double ear infection and had to stop those due to severe diarrhea. LO hasn’t had any since Sunday. Today he’s been fine all day and tonight he ate a new food pouch with Greek yogurt in it. 4 hours later he’s vomiting and I’m not sure if it’s food related or viral. My 2.5 year old did throw up once today but I think she had her fingers in her mouth and gagged because she ate fine all day and was acting completely fine. My 7 month old has vomited about 4 times now and we’re going to get pedialyte now. Our pediatrician seems to think it’s food related but idk what to think. Any insight?