Bad diarrhea but I feel fine?!?

Aside from the stomach cramps, I don't feel ill. But I just had one pretty bad episode of loose stool (this is all TMI sorry) where I literally had to sprint to the bathroom and could barely hold. All I've eaten today was a plain bagel with butter and I drank apple juice and water. I don't feel nauseous, like I have a fever, etc and I was fine all day. But now my stomach cramps are insane and I feel like I can't get up from the toilet. My boyfriend is staying over and I don't want him to know!! 😅 I was extremely stressed from Sunday-last night but I'm not sure why I would just be getting diarrhea now when I'm not stressed anymore?? Any tips?