I think my child may have swallowed something

So my 20 month old was playing on the floor when all of a sudden she started gagging, she grabbed her mouth and then start screaming so I immediately scooped her up and started patting her back. But she was crying so I do t think she was choking. She’d cry for a bit then gag a few times then cry again. She refused her water as she was already so upset. I cuddled her and she seems fine now, since it’s past her nap time she’s fallen asleep in my arms. I’m afraid to leave her in her crib tho because I’m still not sure if she swallowed something or if she did and it’s still in her throat. Her breathing sounds totally fine. I’m not sure what she could have swallowed since I just swept the entire house. She may have found a piece of dog food by our messy dogs kennel or maybe she has a hair in her throat. She seems fine but I’m still super worried. Has something like this ever happened to anyone else?