gagging at the sight of cum 🙊

I'm curious if anyone else has experienced this... sometimes I will start uncontrollably gagging right as my man is cumming. sometimes even if I can't see it... this has happened with a steady partner as well as a first time one but it's not every single time. I'm always worried he will notice because I don't want him to think I'm grossed out because I'm NOT! it's very bizarre 😳