Need help

Newly diagnosed

I’ve been having some real issues today, no blood however I have visited the toilet 6 times today and it’s only 4pm. Diarrhoea for the 3 most recent times. The problem I have is that tomorrow I have a really important practical exam tomorrow which lasts all day at university and I need to attend or I fail. Could I take some diarrhoea tablets to get myself through the day or is that not a good idea?