9 month old making gasping sound

My son has been making this weird gasping noise today. Only occasionally, when he breathes in it sounds kinda like he’s gasping for air. He seems to think it’s funny- when I did the noise back at him he laughed and repeated the noise. I’m still little worried though, of course. He has no other signs of breathing difficulty and no history of asthma or anything like that. He is a very vocal kid, constantly babbling, screaming, and blowing raspberries- is he just exploring his voice? Has anyone else’s LO done this?