Diarrhea after swallowing semen?

Okay this is kind of gross but I’ve noticed this has been happening to me roughly two hours after I swallow my boyfriend’s semen. I don’t think I’m allergic to it because my skin doesn’t get irritated at all when I touch it and I’ve gotten a lot of mixed information from Google. Does this happen to anyone else and if so, is it normal or something I should be concerned about?