Hi
@Myrrhsea
Before you worry about illnesses you may or may not have, here's a link to an NHS hospital's information on Creon:
http://www.christie.nhs.uk/media/4371/432.pdf
You'll see that taking insufficient Creon, particularly with fatty meals and/or snacks leads to diarrhoea. Hopefully by increasing your dose, you will solve the problem. The information sheet explains that you can't actually overdose on Creon, but I recommend that you discuss the correct dose with your GP.
I take Creon because my pancreas is badly damaged: I avoid fatty meals, but I still vary the number of capsules slightly, depending upon the size of the meal. If you follow an LCHF diet, you may need to take more Creon because of the fat content.
I also took the Actimel yoghurt drink each day for a while, which improved my digestion issues. Yakult or a yoghurt with live cultures will probably work just as well.